GOOD MORNING

CONTENTS Introduction

Important terms

History

Philosophies of occlusion

Organization of occlusion

Determinants of occlusal morphology

Importance of occlusal harmony

Treatment goals for occlusion to be in harmony

occlusal equilibration

Occlusal interferences

Occlusal Correction Therapy

Conclusion

References

Introduction

ldquoocrdquo means ldquouprdquo

ldquoclusionrdquo means

ldquoclosingrdquo

ldquoocclusion ldquo means ldquoclosing

uprdquo

ldquo Occlusion means to block to shut in to bring

togetherPrime

(Oxford English Dictionary)

IMPORTANT TERMS

Occlusion

ldquoThe static relationship between incising or masticating surfaces of

maxillary and mandibular teeth or tooth analogues

(GPT 8)

Acc To Ramfjord amp Ash

Occlusion =contact between teeth

ldquoMultifactorial functional relationship between teeth amp other

components of the masticatory system as well as with other areas of

head amp neck that directly or indirectly relate to function

parafunction or dysfunction of the masticatory systemrdquo

Centric occlusion The occlusion of opposing teeth when the mandible is in centric

relation This may or may not coincide with the maximal intercuspal

position

(GPT-8)

Maximum Intercuspation The complete intercuspation of the opposing teeth independent of

condylar position sometimes referred to as the best fit of the teeth

regardless of the condylar position(GPT-8)

Articulation

It is ldquothe static and dynamic contact relationship between

the occlusal surfaces of teeth during functionrdquo

GPT(8)

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

CONTENTS Introduction

Important terms

History

Philosophies of occlusion

Organization of occlusion

Determinants of occlusal morphology

Importance of occlusal harmony

Treatment goals for occlusion to be in harmony

occlusal equilibration

Occlusal interferences

Occlusal Correction Therapy

Conclusion

References

Introduction

ldquoocrdquo means ldquouprdquo

ldquoclusionrdquo means

ldquoclosingrdquo

ldquoocclusion ldquo means ldquoclosing

uprdquo

ldquo Occlusion means to block to shut in to bring

togetherPrime

(Oxford English Dictionary)

IMPORTANT TERMS

Occlusion

ldquoThe static relationship between incising or masticating surfaces of

maxillary and mandibular teeth or tooth analogues

(GPT 8)

Acc To Ramfjord amp Ash

Occlusion =contact between teeth

ldquoMultifactorial functional relationship between teeth amp other

components of the masticatory system as well as with other areas of

head amp neck that directly or indirectly relate to function

parafunction or dysfunction of the masticatory systemrdquo

Centric occlusion The occlusion of opposing teeth when the mandible is in centric

relation This may or may not coincide with the maximal intercuspal

position

(GPT-8)

Maximum Intercuspation The complete intercuspation of the opposing teeth independent of

condylar position sometimes referred to as the best fit of the teeth

regardless of the condylar position(GPT-8)

Articulation

It is ldquothe static and dynamic contact relationship between

the occlusal surfaces of teeth during functionrdquo

GPT(8)

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Introduction

ldquoocrdquo means ldquouprdquo

ldquoclusionrdquo means

ldquoclosingrdquo

ldquoocclusion ldquo means ldquoclosing

uprdquo

ldquo Occlusion means to block to shut in to bring

togetherPrime

(Oxford English Dictionary)

IMPORTANT TERMS

Occlusion

ldquoThe static relationship between incising or masticating surfaces of

maxillary and mandibular teeth or tooth analogues

(GPT 8)

Acc To Ramfjord amp Ash

Occlusion =contact between teeth

ldquoMultifactorial functional relationship between teeth amp other

components of the masticatory system as well as with other areas of

head amp neck that directly or indirectly relate to function

parafunction or dysfunction of the masticatory systemrdquo

Centric occlusion The occlusion of opposing teeth when the mandible is in centric

relation This may or may not coincide with the maximal intercuspal

position

(GPT-8)

Maximum Intercuspation The complete intercuspation of the opposing teeth independent of

condylar position sometimes referred to as the best fit of the teeth

regardless of the condylar position(GPT-8)

Articulation

It is ldquothe static and dynamic contact relationship between

the occlusal surfaces of teeth during functionrdquo

GPT(8)

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

IMPORTANT TERMS

Occlusion

ldquoThe static relationship between incising or masticating surfaces of

maxillary and mandibular teeth or tooth analogues

(GPT 8)

Acc To Ramfjord amp Ash

Occlusion =contact between teeth

ldquoMultifactorial functional relationship between teeth amp other

components of the masticatory system as well as with other areas of

head amp neck that directly or indirectly relate to function

parafunction or dysfunction of the masticatory systemrdquo

Centric occlusion The occlusion of opposing teeth when the mandible is in centric

relation This may or may not coincide with the maximal intercuspal

position

(GPT-8)

Maximum Intercuspation The complete intercuspation of the opposing teeth independent of

condylar position sometimes referred to as the best fit of the teeth

regardless of the condylar position(GPT-8)

Articulation

It is ldquothe static and dynamic contact relationship between

the occlusal surfaces of teeth during functionrdquo

GPT(8)

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Occlusion

ldquoThe static relationship between incising or masticating surfaces of

maxillary and mandibular teeth or tooth analogues

(GPT 8)

Acc To Ramfjord amp Ash

Occlusion =contact between teeth

ldquoMultifactorial functional relationship between teeth amp other

components of the masticatory system as well as with other areas of

head amp neck that directly or indirectly relate to function

parafunction or dysfunction of the masticatory systemrdquo

Centric occlusion The occlusion of opposing teeth when the mandible is in centric

relation This may or may not coincide with the maximal intercuspal

position

(GPT-8)

Maximum Intercuspation The complete intercuspation of the opposing teeth independent of

condylar position sometimes referred to as the best fit of the teeth

regardless of the condylar position(GPT-8)

Articulation

It is ldquothe static and dynamic contact relationship between

the occlusal surfaces of teeth during functionrdquo

GPT(8)

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Acc To Ramfjord amp Ash

Occlusion =contact between teeth

ldquoMultifactorial functional relationship between teeth amp other

components of the masticatory system as well as with other areas of

head amp neck that directly or indirectly relate to function

parafunction or dysfunction of the masticatory systemrdquo

Centric occlusion The occlusion of opposing teeth when the mandible is in centric

relation This may or may not coincide with the maximal intercuspal

position

(GPT-8)

Maximum Intercuspation The complete intercuspation of the opposing teeth independent of

condylar position sometimes referred to as the best fit of the teeth

regardless of the condylar position(GPT-8)

Articulation

It is ldquothe static and dynamic contact relationship between

the occlusal surfaces of teeth during functionrdquo

GPT(8)

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Centric occlusion The occlusion of opposing teeth when the mandible is in centric

relation This may or may not coincide with the maximal intercuspal

position

(GPT-8)

Maximum Intercuspation The complete intercuspation of the opposing teeth independent of

condylar position sometimes referred to as the best fit of the teeth

regardless of the condylar position(GPT-8)

Articulation

It is ldquothe static and dynamic contact relationship between

the occlusal surfaces of teeth during functionrdquo

GPT(8)

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Maximum Intercuspation The complete intercuspation of the opposing teeth independent of

condylar position sometimes referred to as the best fit of the teeth

regardless of the condylar position(GPT-8)

Articulation

It is ldquothe static and dynamic contact relationship between

the occlusal surfaces of teeth during functionrdquo

GPT(8)

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Articulation

It is ldquothe static and dynamic contact relationship between

the occlusal surfaces of teeth during functionrdquo

GPT(8)

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

History

Fictional period (prior

to 1900)

Gliding of teeth

Hypothetical period

(1900-1930)

Edward Hartley Angle

Mathew Cryyer

Calvin Case

BE Lischer Paul Simon

Millo hellman

Factual period (1930 to present )

Concept of dynamic occlusion

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Pioneers like Fuller Clark amp Imerie propagated antagonism amp

meeting or gliding of teeth

Eugene Talbotrsquos text(1900) irregularities of teeth amp their treatment

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Edward angle (1899) ldquogave the key to occlusionrdquo

Mathew Cryyer amp Calvin case

Occlusion refers to the closure of

teeth one upon the other amp

normal dental relations normal

occlusion and typical occlusion

refering to the standard

anatomical occlusion

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

BE Lischer amp Paul Simon (1922)

bullBroadened the concept of occlusion

bullRelated teeth to the rest of the face amp cranium

Milo Hellaman

Advocated racial variation in occlusion

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Based on facts rather than fiction

Holly Broadbent amp Haus Planer (1930) occlusion =

interdigitation of teeth + status of controlling

musculature amp functional factors

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

2 School of thoughts

1 Gnathology

2 Functionalism

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Gnathological concept of occlusion

Dr Beverly B McCollum Father of Gnathology

Dr Harvey Stallard proposed the word Gnathology

Derived from Gnathos jaw + ology study of or knowledge of

Dr McCollum founded the Gnathological Society (1926)

McCollum define Gnathology as

ldquoGnathology is the Science that treats the biologics of the

masticating mechanisms that is the morphology anatomy

histology physiology pathology and the therapeutics of the oral

organ especially the jaws and teeth and the vital relations of the

organ to the rest of the body

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

In 1927 Harvey Stallard recognized that the teeth dictate the arc of

closure and the occluded position of the mandible If articulators were

to be used to reveal mal-occluded teeth then interocclusal records

would be needed to mount the casts in the centric relation position

In 1930 Dr Charles Stuart and Dr McCollum developed the first

semi-adjustable articulator called the McCollum Gnathoscope

In 1934 with the aid of Dr Stuart McCollum produced the first

mandibular movement recorder known as the McCollum Gnathograph

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

ARNE G LAURITZEN

Direction of occlusal stresses located close to the long axis of teeth ndash allows

restoration of dentition in max Intercuspation at centric relation position

Occlusal loads fall on as great no Of teeth as possible

Optimal tooth-to-tooth occlusion should reach terminal hinge-axis

intercuspation without interferences

Ideal relations obtained with canine-guided occlusion

Group contact bw upper amp lower anterior teeth during protrusive

movement

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

NILES GUICHET amp GNATHOLOGY

Explained adv Of canine guidance by means of biomechanics

Denar articulator was used

Concept followed ndash canines have a mechanical adv of standing

lateral stress 8 times than 2nd premolars

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

FREEDOM IN CENTRIC CONCEPT

POSSELT ndash 1st to describe its principles

Functional occlusion ndash support from Ramfjord amp

Ash

Max Intercuspation amp centric relation are

concident but flat areas on the depth of fossae

on which opposing cusps occlude will allow for a

certain degree of freedom in both centric amp

eccentric movements without guiding influences

of occlusal inclines

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

PANKEY MANN-SCHUYLER CONCEPT

Obj optimal health masticatory effeciency comfort amp esthetics

Characteristics

i Stable amp static contacts over greatest no Of teeth in centric relation

ii Long centric

iii Group function during lateral excursions

iv No contact on balancing side

v During protrusive movements an immediate disocclusion of post Teeth might occur

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

DAWSONrsquoS CONCEPT

CRITERIA FOR IDEAL OCCLUSION

i Stable contacts on all teeth at the level of centric relation with

positioning of condyles at highest point aganist eminentia

ii Anterior guidance must be in harmony with border movements of envelope of motion

iii Disocclusion of all post Teeth during protrusive movements amp on balancing side

iv Gp Function on working side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

For development of an ideal occlusion ant Teeth are more capable of

supporting stress than posterior brsquocoz of

1 Mechanical position in relation to the fulcrum (tmj) amp force

(masticatory muscles)

2 Higher density of bone surrounding ant Long roots

3 Better crown to root ratio

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Dawson presented his theory of ldquonutcrackerrdquo

The nut ldquoant Teethrdquo is from fulcrum (condyles) lesser would be the

force exerted on the nut

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

European conceptual model

Also ka Gerberrsquos Condylar Displacement Theory

Any deviation related to this mandibular centralization

constitutes a condylar displacement

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Concepts of occlusion

Bilaterally balanced occlusion

Not used in FPD

Unilaterally balanced occlusion

Group function

Mutually protected occlusion

Anterior protected articulation

Canine protected articulation

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Bilaterally balanced occlusion

Based on the work of Von Spee amp Monson

Not used in fixed prosthodontics today

It states that a maximum numbers of teeth should contact in all

exursive positions of mandible

Advantages

Useful in complete denture

Increases stability

Disadvantages

Increases rate of occlusal wear

Accelerated periodontal breakdown

Neuromuscular disturbances

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Unilaterally balanced occlusion Group Function

Its origin is in the work of Schuyler

ldquoWho demonstrated the destuctive nature of tooth contacts on the non-working side and

concluded cross-arch balance not required in natural teethrdquo

Teeth on non- working side are not in contact

Most desirable group function consists of canines premolars amp sometimes the mesio-buccal cusp

of the first molar on the working side

Any laterotrusive contacts more posterior than the mesial portion of the first molar are not

desirable because of the increased amount of force that can be placed as they are near the fulcrum

and force vectors

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Advantages

Distributes occlusal loads better

Absence of contacts on non-working side prevents those teeth from

being subjected to the destructive

Saves centric holding cusps from excessive wear

Maintains occlusion

Disadvantages

Excessive load on posterior teeth of working side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Mutually Protected Occlusion

During the early 1960rsquos the occlusal scheme called Mutually

Protected Occlusion was advocated by Stuart amp Stallard

Based on earlier work of DrsquoAmico

This concept states that anterior teeth bear all the load and posterior

teeth are disoccluded in any excursive position of the mandible

Centric relation coincide with maximum intercuspation

Anterior teeth contact very lightly or slightly out of contact (approx25

micron)

Anterior teeth protect posterior teeth in excursions amp post Teeth

protects ant Teeth in intercuspation

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

An occlusal scheme in which the posterior teeth prevent

excessive contact of the anterior teeth in maximum

intercuspation and the anterior teeth disengage the posterior

teeth in all mandibular excursive movements Alternatively

an occlusal scheme in which the anterior teeth disengage the

posterior teeth in all mandibular excursive movements and

the posterior teeth prevent excessive contact of the anterior

teeth in maximum intercuspation

( GPT -8)

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

FRONTAL VEIW WITH MOLARS IN CENTRIC RELATION

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

LATERAL EXCURSION

CONTACT ON WORKING SIDE

DIS OCCLUSION ON NON WORKING SIDE

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

CENTRIC OCCLUSION VIEWED LATERALLY

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

IN PROTUSION ONLY MAXILLARY AND MANDIBULAR INCISORS ARE IN CONTACT

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Also ka ORGANIC OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the anterior teeth disengages the posterior teeth

in all mandibular excursive movements(GPT-8)

Centric relation position and maximum intercuspation are coincident

The posterior teeth are in a cusp ndash fossa relationship one tooth to one

tooth contact

ANTERIOR PROTECTED ARTICULATION

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Each functional cusp contacts the occlusal fossa at 3 points

while the anterior teeth disocclude

In protusive movement the maxillary 4 incisors guide the

mandible and disclude the posterior teeth (Boderson 1978)

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Also ka CANINE GUIDED OCCLUSION

A form of mutually protected articulation in which the vertical and

horizontal overlap of the canine teeth disengage the posterior teeth

in the excursive movements of the mandible

(GPT-8)

CANINE PROTECTED OCCLUSION

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Canine acts as naturersquos stress ndash breaker

Mandibular eccentric movements are guided by the canines except in

protusive movement so the canine are a key element in occlusion

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Nicely aligned teeth

Cuspid rise - right side

No posterior teeth in contact

During crossover guidance is from anterior teeth

During crossover none of the posterior teeth on other side are contacting either

Cuspid rise in other direction No posterior contacts

Canine- Guided

Occlusion

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

CANINE GUIDANCE ON WORKING SIDE

NO CONTACTS ON NON-WORKING SIDE IN LATERAL EXCURSION

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

LINGUAL VIEW OF THE CANINE RISE LINGUAL VIEW OF THE CANINE RISE

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

ANATOMICAL EVIDENCE IN SUPPORT OF CANINE GUIDED OCCLUSION

Canines are best suited to accept horizontal forces because-

Longest amp largest roots

Best crown-root ratio

Surrounded by dense compact bone

the location far from TMJ

Many receptors are present in the periodontal ligament so it

controls lateral pressure by directing vertical masticatory

movements

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Advantages-

Absence of frictional wear

Minimizes horizontal loading of post Teeth as they come in contact at

the very end of chewing stroke

In intercuspation no obliquely directed forces on anterior teeth

Ease of fabrication

Greater tolerance by patients

Disadvantages

Good periodontal health of anterior teeth must

Anglersquos class II or III can not be guided by ant Teeth

Cannot be used in Crossbite situations

Missing prosthetic canine

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Posterior determinants Right amp left TMJ amp associated structures

Posterior determinants of occlusion A Angle of the articular eminence (condylar guidance angle) 1 Flat 2 average 3 steep B Anatomy of the medial walls of the mandibular fossae 1 Greater than average 2 average 3 minimal sideshift

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

A shallow protrusive condylar inclination requires short cusps (A) while a steeper path permits the cusps to be longer(B)

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

A pronounced immediate lateral translation requires that the cusps to be short (A) while gradual lateral translation allows the cusps to be longer (B)

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

The angle between the working (W)and the non-working path(NW) is greater on teeth located farther from the condyle

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Anterior Determinants

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

PATIENT ADAPTABILITY There may be differences in the adaptive response of a patient to

occlusal abnormalities

Individuals with a lower threshold will be unable to tolerate even trivial

occlusal deficiencies

Patient with raised threshold may adapt to distinct malocclusions

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

IMPORTANCE OF OCCLUSAL HARMONY

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Ideal mandibular function results from a harmonious relationship of all

the muscles that move the jaws

If intercuspation of tooth is not in harmony with the joint- ligament-

muscle balance a stressful and tiresome protective role is forced onto

the muscle

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Williamson using EMG procedures showed that

interfering contacts on posterior teeth in any eccentric

position causes hyperactivity of the elevator muscles

(JPD 198349816-823)

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Mongini showed direct relationship between the shape of

the condyle after remodelling amp abrasion patterns on the

teeth

Muscles must have complete freedom to function with no

extended demands on any muscle or group of muscles

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Ligaments must be permitted to assume their bracing roles

to permit muscles to rest

If occlusion is in harmony then least horizontal stresses

fall on teeth

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

IF OCCLUSION IS NOT IN HARMONY

Pain tenderness

Teeth may exhibit hypermobility open

contacts or abnormal wear

Widened periodontal ligament space

Periodontal defects

Extensive bone loss

Rapid tooth migration

Widened periodontal ligament space and increased mobility of mandibular molars Occlusal premature contacts were noted in lateral and protrusive movements

Unstable occlusion

Removal of a tooth without

replacement has led to tilting and drifting

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

Bruxism amp clenching

Muscle spasm amp pain

Excessive deviation in closing amp opening

of mandible due to asymmetric muscle

activity

Restricted opening amp trismus due to

mandibular elevator muscles spasm

Pain clicking or popping in TMJ

Midline deviation during opening and closing movements can be indicative of asymmetric muscle activity or joint derangement Here during opening less than optimal translation occurs on the patients left side

MYOFACIAL PAIN DYSFUNCTION ndash

Diffuse unilateral pain in pre-auricular area with muscle tenderness

clicking or popping noises in the contra lateral TMJ amp limitation of jaw

function

TREATMENT GOALS FOR OCCLUSION TO BE IN HARMONY

The Objectives of occlusal treatment are as follows

1 To direct the occlusal forces along the long axes of the teeth

2 To attain simultaneous contact of all teeth in centric relation

3 To eliminate any occlusal contact on inclined planes to enhance the

positional stability of the teeth

4 To have centric relation coincide with the maximum intercuspation

position

5 To arrive at the occlusal scheme selected for the patient (eg unilateral

balanced versus mutually protected)

Occlusal treatment should be-

tooth movement through orthodontics

elimination of deflective occlusal contacts

through selective reshaping of the occlusal

surfaces of teeth

the restoration and replacement of missing

teeth resulting in more favorable distribution

of occlusal force

The modification of the occlusal form of the teeth with the

intent of equalizing occlusal stress producing

simultaneous occlusal contacts or harmonizing cuspal

relations

( GPT 8)

EQUILIBRATION PROCEDURES

1 Reduction of all contacting tooth surfaces that interfere

with terminal hinge axis closure

2 Selective reduction of tooth structure that interferes

with lateral excursions

3 Elimination of all post tooth structure that interferes

with protrusive excursions

4 Harmonization of ant guidance

Interferences are undesirable occlusal contacts that may

produce mandibular deviation during closure to maximum

intercuspation or may hinder smooth passage to and from

the intercuspal position

(GPT-8)

Types of occlusal interferences

1 Centric 2 Lateral

Working

Nonworking

Protrusive

LOCATING OCCLUSAL INTERFERENCES

The centric relation position for each condyle must be

confirmed before tooth contacts are marked

Firm pressure must be used to test the position

Pressure should not be applied until after the condyles have

been gently manipulated to the suspected CR seat

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

TREATMENT GOALS FOR OCCLUSION TO BE IN HARMONY

The Objectives of occlusal treatment are as follows

1 To direct the occlusal forces along the long axes of the teeth

2 To attain simultaneous contact of all teeth in centric relation

3 To eliminate any occlusal contact on inclined planes to enhance the

positional stability of the teeth

4 To have centric relation coincide with the maximum intercuspation

position

5 To arrive at the occlusal scheme selected for the patient (eg unilateral

balanced versus mutually protected)

Occlusal treatment should be-

tooth movement through orthodontics

elimination of deflective occlusal contacts

through selective reshaping of the occlusal

surfaces of teeth

the restoration and replacement of missing

teeth resulting in more favorable distribution

of occlusal force

The modification of the occlusal form of the teeth with the

intent of equalizing occlusal stress producing

simultaneous occlusal contacts or harmonizing cuspal

relations

( GPT 8)

EQUILIBRATION PROCEDURES

1 Reduction of all contacting tooth surfaces that interfere

with terminal hinge axis closure

2 Selective reduction of tooth structure that interferes

with lateral excursions

3 Elimination of all post tooth structure that interferes

with protrusive excursions

4 Harmonization of ant guidance

Interferences are undesirable occlusal contacts that may

produce mandibular deviation during closure to maximum

intercuspation or may hinder smooth passage to and from

the intercuspal position

(GPT-8)

Types of occlusal interferences

1 Centric 2 Lateral

Working

Nonworking

Protrusive

LOCATING OCCLUSAL INTERFERENCES

The centric relation position for each condyle must be

confirmed before tooth contacts are marked

Firm pressure must be used to test the position

Pressure should not be applied until after the condyles have

been gently manipulated to the suspected CR seat

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

The Objectives of occlusal treatment are as follows

1 To direct the occlusal forces along the long axes of the teeth

2 To attain simultaneous contact of all teeth in centric relation

3 To eliminate any occlusal contact on inclined planes to enhance the

positional stability of the teeth

4 To have centric relation coincide with the maximum intercuspation

position

5 To arrive at the occlusal scheme selected for the patient (eg unilateral

balanced versus mutually protected)

Occlusal treatment should be-

tooth movement through orthodontics

elimination of deflective occlusal contacts

through selective reshaping of the occlusal

surfaces of teeth

the restoration and replacement of missing

teeth resulting in more favorable distribution

of occlusal force

The modification of the occlusal form of the teeth with the

intent of equalizing occlusal stress producing

simultaneous occlusal contacts or harmonizing cuspal

relations

( GPT 8)

EQUILIBRATION PROCEDURES

1 Reduction of all contacting tooth surfaces that interfere

with terminal hinge axis closure

2 Selective reduction of tooth structure that interferes

with lateral excursions

3 Elimination of all post tooth structure that interferes

with protrusive excursions

4 Harmonization of ant guidance

Interferences are undesirable occlusal contacts that may

produce mandibular deviation during closure to maximum

intercuspation or may hinder smooth passage to and from

the intercuspal position

(GPT-8)

Types of occlusal interferences

1 Centric 2 Lateral

Working

Nonworking

Protrusive

LOCATING OCCLUSAL INTERFERENCES

The centric relation position for each condyle must be

confirmed before tooth contacts are marked

Firm pressure must be used to test the position

Pressure should not be applied until after the condyles have

been gently manipulated to the suspected CR seat

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Occlusal treatment should be-

tooth movement through orthodontics

elimination of deflective occlusal contacts

through selective reshaping of the occlusal

surfaces of teeth

the restoration and replacement of missing

teeth resulting in more favorable distribution

of occlusal force

The modification of the occlusal form of the teeth with the

intent of equalizing occlusal stress producing

simultaneous occlusal contacts or harmonizing cuspal

relations

( GPT 8)

EQUILIBRATION PROCEDURES

1 Reduction of all contacting tooth surfaces that interfere

with terminal hinge axis closure

2 Selective reduction of tooth structure that interferes

with lateral excursions

3 Elimination of all post tooth structure that interferes

with protrusive excursions

4 Harmonization of ant guidance

Interferences are undesirable occlusal contacts that may

produce mandibular deviation during closure to maximum

intercuspation or may hinder smooth passage to and from

the intercuspal position

(GPT-8)

Types of occlusal interferences

1 Centric 2 Lateral

Working

Nonworking

Protrusive

LOCATING OCCLUSAL INTERFERENCES

The centric relation position for each condyle must be

confirmed before tooth contacts are marked

Firm pressure must be used to test the position

Pressure should not be applied until after the condyles have

been gently manipulated to the suspected CR seat

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

The modification of the occlusal form of the teeth with the

intent of equalizing occlusal stress producing

simultaneous occlusal contacts or harmonizing cuspal

relations

( GPT 8)

EQUILIBRATION PROCEDURES

1 Reduction of all contacting tooth surfaces that interfere

with terminal hinge axis closure

2 Selective reduction of tooth structure that interferes

with lateral excursions

3 Elimination of all post tooth structure that interferes

with protrusive excursions

4 Harmonization of ant guidance

Interferences are undesirable occlusal contacts that may

produce mandibular deviation during closure to maximum

intercuspation or may hinder smooth passage to and from

the intercuspal position

(GPT-8)

Types of occlusal interferences

1 Centric 2 Lateral

Working

Nonworking

Protrusive

LOCATING OCCLUSAL INTERFERENCES

The centric relation position for each condyle must be

confirmed before tooth contacts are marked

Firm pressure must be used to test the position

Pressure should not be applied until after the condyles have

been gently manipulated to the suspected CR seat

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

EQUILIBRATION PROCEDURES

1 Reduction of all contacting tooth surfaces that interfere

with terminal hinge axis closure

2 Selective reduction of tooth structure that interferes

with lateral excursions

3 Elimination of all post tooth structure that interferes

with protrusive excursions

4 Harmonization of ant guidance

Interferences are undesirable occlusal contacts that may

produce mandibular deviation during closure to maximum

intercuspation or may hinder smooth passage to and from

the intercuspal position

(GPT-8)

Types of occlusal interferences

1 Centric 2 Lateral

Working

Nonworking

Protrusive

LOCATING OCCLUSAL INTERFERENCES

The centric relation position for each condyle must be

confirmed before tooth contacts are marked

Firm pressure must be used to test the position

Pressure should not be applied until after the condyles have

been gently manipulated to the suspected CR seat

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Interferences are undesirable occlusal contacts that may

produce mandibular deviation during closure to maximum

intercuspation or may hinder smooth passage to and from

the intercuspal position

(GPT-8)

Types of occlusal interferences

1 Centric 2 Lateral

Working

Nonworking

Protrusive

LOCATING OCCLUSAL INTERFERENCES

The centric relation position for each condyle must be

confirmed before tooth contacts are marked

Firm pressure must be used to test the position

Pressure should not be applied until after the condyles have

been gently manipulated to the suspected CR seat

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Types of occlusal interferences

1 Centric 2 Lateral

Working

Nonworking

Protrusive

LOCATING OCCLUSAL INTERFERENCES

The centric relation position for each condyle must be

confirmed before tooth contacts are marked

Firm pressure must be used to test the position

Pressure should not be applied until after the condyles have

been gently manipulated to the suspected CR seat

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

LOCATING OCCLUSAL INTERFERENCES

The centric relation position for each condyle must be

confirmed before tooth contacts are marked

Firm pressure must be used to test the position

Pressure should not be applied until after the condyles have

been gently manipulated to the suspected CR seat

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Loading pressure should be directed to seat the condyles against

the eminence while firm upward pressure is also being applied

Distalization of condyles should be avoided

CRndash located at open position

Now hold mandible on its terminal axis amp close on that arc by

increments of a mm or two at a time

Continue a slow opening ndashclosing movement until the first tooth

contact occurs ndash 1st INTERFERENCE

Let pt Feel the first contact hold that position for a sec amp Then

squeeze ndash it determines direction amp degree of lsquoslidersquo from CR

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

The CENTRIC INTERFERENCE is a premature contact --

occurs when the mandible closes with the condyles in their optimum

position in the glenoid fossae

It will cause deflection of the mandible in a posterior anterior andor lateral

direction

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

ELIMINATING INTERFERENCES TO CENTRIC RELATION

Differentiated into two types

1 INTERFERENCES TO THE ARC OF CLOSURE

2 INTERFERENCES TO THE LINE OF CLOSURE

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

If the patient slides his mandible to obtain tight closure it indicates the presence of occlusal discrepancies

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

INTERFERENCE TO THE ARC OF CLOSURE

As condyles rotate on their terminal hinge axis each lower tooth follow

an arc of closure all the way to the most closed occlusal position

without any deviation off this arc

Any tooth structure that interferes with this closing arc has the effect of

displacing the mandible forward of interference to reach the most

closed occlusal position

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Primary interferences that deviate the condyle forward produce

Anterior Slide

CORRECTION -

lsquoMUDLrsquo Grind the mesial inclines of upper teeth or distal

inclines of lower teeth

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

INTERFERENCE TO LINE OF CLOSURE

Interferences that cause mandible to deviate

to left or right from 1st point of contact to

most closed position

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Grinding rules are

1 Interfering incline causing mand To deviate off the line of closure

towards the cheek

Grind the buccal incline of the upper or the lingual incline

of the lower or both inclines

2 If interfering incline causes the mandible to deviate off the line of

closure towards the tongue

Grind the lingual incline of upper or buccal incline of lower or

both inclines

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

If interferences produce deviations off both arc of closure amp the line of

closure at same time

Upper inclines are adjusted on inclines that face the same

direction as slide

Lower teeth are adjusted by grinding off inclines that face the

opposite direction from path of slide

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

LATERAL EXCURSION INTERFERENCES

Path followed by lower posterior teeth as they leave CR amp

travel laterally is dictated by

1 Border movements of condyle which act as the post

Determinant

2 Anterior guidance which act as ant Determinant

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

A WORKING INTERFERENCE

may occur when there is contact between the maxillary and mandibular

posterior teeth on the same side of the arches as the direction in which the

mandible has moved

If that contact is heavy enough to disocclude anterior teeth it is an

interference

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

A NONWORKING INTERFERENCE is an occlusal contact

between maxillary and mandibular teeth on the side of the arches opposite the

direction in which the mandible has moved in a lateral excursion

The nonworking interference is of a particularly destructive nature

The potential for damaging the masticatory apparatus has been attributed to

changes in the mandibular leverage the placement of forces outside the long

axes of the teeth and disruption of normal muscle function

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

LOCATING LATERAL INTERFERENCES Manipulate mand To CR

Teeth to be closed on terminal axis arc until they contact hold onto

this position

On working side thumb is released amp all 4 fingers used to exert upward

pressure on working condyle

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

On balancing side ndash pressure to be exerted towards working condyle

While maintaining pressure with both hands ask pt To slide jaw to left

or right

Assistant should insert marking ribbon in dry mouth to record

interferences

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

ELIMINATING LATERAL INTERFERENCES

Balancing side interferences ndash

Eliminate all contact on inclines as soon as lower teeth move out of

CR amp start towards the tongue

Grinding rule

lsquoBULLrsquo - grind the buccal inclines of upper or lingual inclines

of lower

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Protrusive interferences

A premature contact

Only front teeth should touch in protrusive excursions

Occurring between the mesial aspects of mandibular posterior teeth and the

distal aspects of maxillary posterior teeth

Grinding rule ndash lsquoDUMLrsquo grind

distal inclines of upper or

mesial incline of lower teeth

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Occlusal splints occlusal appliances or orthotics

Used extensively in the management of TMJ disorder amp bruxism

Helpful in determining where a proposed change in a patientrsquos occlusal

scheme will be tolerated

Fabricated in an acrylic resin overlay

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Fabrication of the device-

Direct procedure with a vacuum-formed

matrix(autopolymerized)

Indirect procedure with autopolymerizing acrylic

resin

Indirect procedure with heat-polymerized acrylic

resin

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

CONCLUSION

Most restorative procedures affect the shape of occlusal surfaces

Proper dental care ensures that functional contact relationships are

restored in harmony with both dynamic amp static conditions

Therefore maxillary amp mandibular teeth should contact to allow

optimum function minimal trauma to supporting structures amp an

even load distribution throughout dentition

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

References

Books

Iven klinebergrob jagger Occlusion And Clinical Practice-an Evidence-based Approach

John Dos Santos Jr Occlusion- Principles amp concepts

Dawson functional occlusion From TMJ To Smile Design

Dawson Evaluation diagnosis amp treatment of occlusal problems

Okeson

Shillingburg Hobo Whitsett Jacobi Brackett Fundamentals Of Fixed Prosthodontics

Rosensteil Land Fujimoto Contemporary Fixed Prosthodontics

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724

Journals

JPD198349816-823

Ogawa Ogimoto Pattern Of Occlusal Contacts In Lateral Position

JPD 19988067

Schuyler Factors of Occlusion As Applicable To Restorative

Dentistry JPD 19533 772-715

Pokorny WeinsLivtak Occlusion For Fixed Prosthodontics ndash A

Historical Perspective of the Gnathological Influence JPD

200899299-313

Johnson Variations in Organic Occlusion JPD 197941625-629

Clark Evans Functional Occlusion A Review JO 200128176-81

Stuart Good Occlusion For Natural Teeth JPD 196414716-724