class ii div 2 malocclusion

CLASS II DIV 2 MALOCCLUSION

Presented by: Ahmed Saeed Baattiah

Under supervision of: Prof. Maher Fouda

Mansoura UniversityFaculty of Dentistry

Orthodontics Department

Father of modern orthodontics

Born on a farm in Pennsylvania on June 1 , 1855 - fifth of seven children.

Marked ability to improve & create mechanical equipment on the farm.

Apprenticed him self to a dentist at his mothers request.

Graduated from Pennsylvania college of Dentistry – 1878.

Classified malocclusion – 1899.

Established orthodontics as a separate branch of dentistry.

Established Angle School Of Orthodontics in 1900.

Founded American Society Of Orthodontics in 1901.

Developed different orthodontic appliances.

INTRODUCTION

ETIOLOGY

CLASSIFICATION

FEATURES

TREATMENT

DIAGNOSIS

CONTENETS

MUSCULAR PATTERN

INTRODUCTION Orthodontic specialty deals with various malocclusions. Malocclusion is the study of its cause or causes. Development of normal dentition and occlusion depends on number of interrelated factors that include the dentoalveolar, skeletal and neuromuscular factor .

CLASS II DIVISION 2 MALOCCLUSION

CLASS II DIVISION 2

DEFINITION

INTRODUCTION

Class II division 2 malocclusion is a type of class II malocclusion, defined by Angle in 1899.

It represents 5 to 10 % of all malocclusion ( Sassouni 1971 ).

INTRODUCTION

ETIOLOGY

CLASSIFICATION

FEATURES

TREATMENT

DIAGNOSIS

CONTENETS

MUSCULAR PATTERN

Shape of the head : brachycephalic

Facial profile: convex

Chin: prominent

Lower lip: Everted ( lower lip line is high relative to the upper incisors)

Upper lip: Positioned high inrespect to the upper anteriors (Gummy smile)

Mentolabial sulcus: Deep

Mentalis: Hyperactive

Retrusive lips

Facial features

Gummy smile

Prominent chinHyper active mentalis

Facial profile of class II division 2

The lips are usually thin and there is a lack of vertical development of the face below the nose.

The masseter and temporalis muscles are wide.

Mild mandibular retrognathia, with a pronounced chin point and reduced lower anterior face height.

High lower lip line

Some features of Class II division 2 malocclusion

Retroclined maxillary central incisors and deep overbite.

Profile of a class II division 2 boy. A round face, backwardly held mandible with thick chin button and thin lips.

Dental features

Class II molar and canine relationship

Deep traumatic bite Retroclined upper four incisors or

retroclined centrals with labial inclination of the laterals.

The tooth size may be small, and upper

incisors may have decreased collum angle between the crown and the root.

Decrease over jet

Shorter root and longer crown.

gingival recession

Canine relationship

Molar relationship

Angle class II division 2 malocclusion

Deep bite : overclosure ( closed bite ) Class II div 2 with posterior open bite

The lower teeth are shifted backward compared to the upper teeth (red arrow)

The green arrows indicate a bone loss problem (periodontics).

The upper left canine is longer than the right canine (blue line) and will have to be levelled individually to avoid causing inclination of the anterior occlusal plane.

Class II division 2, mandibular retrognathia and supraocclusion

Initial facial and intraoral photographs

Cephalometric features

Class ll/division 2 malocclusions have a shorter or normal mandibular length with its sagittal position retruded.

The chin being prominent and posterior facial height definitely increased.

The mandibular growth vector is horizontally oriented, with a flat mandibular plane, giving the appearance of a hypodivergent facial pattern.

The gonial angle is acute.

The lower incisors have a normal inclination relative to the mandibular plane but are retroclined relative to various facial planes.

Interincisal angle is obtuse, overbite is deep.

Airway restriction at the oropharynx level

Backward shift of the lower jaw

Upper incisor too vertical



Proclined lateral incisor

Retroclined central incisor

Flat mandibular plane, anticlockwise rotation

Increase in posterior face height

Class II division 2 incisors have a shorter root, a longer crown


Anthropometric method used in determination of gonial angle

GONIAL ANGLE

GONIAL ANGLE

Reduced gonial angle

Orthopantomograph (OPG) of Class II division 2 malocclusion. Well developed ramus in width with short gonial angle

INTRODUCTION

ETIOLOGY

CLASSIFICATION

FEATURES

TREATMENT

DIAGNOSIS

CONTENETS

MUSCULAR PATTERN

Diagnosis

Class II division 2 Extra and intra oral photographs

INTRODUCTION

ETIOLOGY

CLASSIFICATION

FEATURES

TREATMENT

DIAGNOSIS

CONTENETS

MUSCULAR PATTERN

Angle’s classification

British standards classification

Von - Der - Linden classification

Type A:*Maxillary central incisors and laterals are retroclined.*Degree of retroclination is less severe in nature.


Type B:Maxillary lateral incisors are overlapping the retroclined maxillary central incisors.


Type C:*Maxillary central and lateral incisors are retroclined and are overlapped by the maxillary canines.

INTRODUCTION

ETIOLOGY

CLASSIFICATION

FEATURES

TREATMENT

DIAGNOSIS

CONTENETS

MUSCULAR PATTERN

Muscular pattern Class II Division 2 TMJ Problems

Strong muscular pattern may not permit the bite opening with the vertical increase of the buccal segment in adult patients.

Abnormal intercuspal masticatory articulations

physiologic changes at any postural level require compensatory neuromuscular accommodation. Clinical evidence has consistently shown the occlusal signs and muscular symptoms that occur over time when teeth are not able to take their optimal physiologic place (position) within the oral cavity. Various musculoskeletal problems will occur.

Class II Division 2 TMJ Problems

Note: No gonial angle notching, nor extra boney growth exists with this 18 year old male. Normal vertical dimension of teeth supporting healthy musculature with no muscle tenderness or TMD symptoms. Normal mandibular range of motion is exhibited with no clicking or popping joints.

Normal mandibular range of motion is exhibited with no clicking or popping joints.

Because of these compressing forces the mandible retrudes while the masticatory muscles strain and skew the underlying bony structures of the cranium, mandibular condyles, cervical neck bones and downward.

Every TMD patient is a walking example of the ill effects of the mal alignment of the postural system beginning with vertically under developed (or under erupted) molars and bicuspids. this contributes to narrowing of dental arches, insufficient room for the tongue and further results in a downward cascading effect of jaw collapse, abnormal head posturing, and degeneration on the temporomandibular joints (due to abnormal forces (lack of sufficient vertical occlusal support).

INTRODUCTION

ETIOLOGY

CLASSIFICATION

FEATURES

TREATMENT

DIAGNOSIS

CONTENETS

MUSCULAR PATTERN

Class II division 2 malocclusion arise from a number of interrelated dental, skeletal, soft tissue and genetic factors.

Most of class II/2 malocclusion are caused by an underlying skeletal discrepancy, and few have a normal skeletal jaw relationship.

Etiology

Soft tissues

Skeletal pattern

Dental factors

Etiology

Etiology

Dental class II division 2

Normal maxilla-mandibular skeletal relationship. Steiner : SNA,SNB,ANB = Normal

Mainly occurs due to mesial drift of the maxillary first molar . As a result of

a) Loss of mesial proximal contact with the primary 2nd molar - premature extraction/loss of primary 2nd molar. - congenitally missing primary 2nd molar.

b) inter-arch tooth size discrepancy - small or congenitally missing maxillary permanent teeth (2nd premolar) results in a class II molar relation.

c) Maxillary canine or 2nd premolar impaction or displacement out of the arch - inadequate space in the dental arch class II molar

Dental class II division 2

Soft tissues

Skeletal pattern

Dental factors

Etiology

Etiology

Skeletal class II division 2 Result from a discrepancy in the maxillary-mandibular skeletal relationship.

It might be either due to: 1) Mandibular deficiency 2) Maxillary excess 3) or a combination of both

Skeletal class II division 2 Mandibular deficiency

It is a skeletal class II relationship resulting from a mandibular that is either small or retruded relative to the maxilla.

Mandibular deficiency

size Position (Small mandible) ( Retrusion of a normal

sized mandible)

OR

(Combination of both in severe cases )


Class II div 2 with a small mandible the decreased size is localized more to the mandibular body ( Mandibular Ramus is of normal length ).


Mandibular deficiency may result from the retrusion ( distal positioning ) of a normal – sized mandible.

Cephalometric analysis showed a skeletal class II relationship : ANB angle = 9SNA = 82B point was retruded, SNB angle = 74

Skeletal class II division 2 Maxillary excess


Vertical maxillary excess may be localized only to the posterior area Open bite and incompetent lips ( normal vertical display of maxillary incisors in repose and during smiling ).

0verall maxillary excess includes both the anterior and the posterior area resulting in an excessive vertical display of the maxillary incisors in repose and during smiling (high smile line )

Gummy smile and incompetent lips.

In these 2 conditions of maxillary excess Mandible is rotated downward and posteriorly (clockwise) resulting in a class II skeletal relationship.


Class II /2 with an overall vertical maxillary excess:


Maxillary excess in Ant-Post Dimension is characterized by a protrusion of the entire midface including : 1) Nose 2) infra orbital area 3) upper lip

Skeletal class II division 2 combination

Skeletal class II division 2 might be a combination of both mandibular deficiency and maxillary excess.

Which will add to the severity of the Ant-post skeletal problem

A patient with maxillary vertical excess and mandibular deficiency

Skeletal class II division 2

Soft tissues

Skeletal pattern

Dental factors

Etiology

Etiology

Soft tissues

If the lower facial height is reduced

the lower lip line will effectively be higher relative to the crown of the upper incisors (more than the normal one-third coverage.

A high lower lip line will tend to retrocline the upper incisors

High lip line cause retroclination to incisors

Soft tissues

Patient with bimaxillary retroclination due to lip action Soft tissues

In some cases the upper lateral incisors, which have a shorter crown length, will escape the action of the lower lip and therefore lie at an average inclination, whereas the central incisors are retroclined.

Soft tissues

INTRODUCTION

ETIOLOGY

CLASSIFICATION

FEATURES

TREATMENT

DIAGNOSIS

CONTENETS

MUSCULAR PATTERN

Treatment of Class II Division 2

Treatment option for dental Class II Division 2

For a dental Class II/2 malocclusion:

Treatment option for skeletal Class II Division 2

Treatment for skeletal Class II Division 2

The goal of growth modification is to enhance the unacceptable skeletal relationship by modifying remaining facial growth pattern of the jaws.

Optimum timing : pre-pubertal growth spurt ( active growth period)


High pull headgear ( parietal )

Distal and intrusive forces on the maxillary molar.

Extra-oral force is directed superior and posterior.

A-p and vertical maxillary excess ( decreased V.D).

High pull headgear ( parietal )

Treatment option for skeletal Class II Division 2Treatment for skeletal Class II Division 2

Low pull headgear ( cervical )

Distal and extrusive forces on maxillary molars.

Posterior and inferior extra-oral force

Increases vertical dimension

Used in A-P maxillary excess with flat mand.plane

Low pull headgear ( cervical )

Medium pull headgear ( occipital )

Headgear to upper part of the Twin block

J-hook headgear

J-hook High-Pull Headgear

REMOVABLE FUNCTIONAL APPLIANCES

ACTIVATORBIONATOR

TWIN BLOCK

FRANKYL II

FIXED FUNCTIONAL APPLIANCES

Herbst appliance Jasper jumper

Adult patient with nearly full-cusp Class II molar relationship. Note inclination of incisors, 100% deep bite, and discrepancy in gingival margins between canines and incisors.

Biomechanical Considerations

Treatment of Class II, Division 2 Malocclusion in Adults by dental camouflage

Intrusion arch produces anterior tipback moment and intrusive force along with extrusive force on molars.

Force system and ligation points of intrusion arch in Class II, division 2 malocclusion.

Canine retraction generates extrusive effect on incisors. To counteract this tendency, intrusion arch is tied anteriorly.

Canine retraction with .016" × .022" stainless steel base arch and overlay intrusion arch for anchorage and incisor control.

Moment at molar counteracts mesial reactive force in anchor unit.

A. Mushroom-loop archwire without preactivation bends. B. Archwire with gable bends mesial and distal to archwire. C. 3mm preactivation of loop

017" × .025" CNA mushroom-loop archwire after intraoral activation

A. Mushroom-loop archwire with spaces closed. Wire is left in place for another six weeks to allow residual moments to deliver proper axial root inclinations.

B. Same patient with ideal axial inclinations

B. After initial intrusion phase (note incisor level and molar tipback), .016" × .022" stainless steel base arch is used with short .017" × .025" nickel titanium intrusion arch to retract canines.

C. Canines fully retracted into Class I positions. Note intrusion, overbite, and anchorage control without elastic wear.

017" × .025" mushroom-loop archwire with preactivation bends activated about 4mm for translatory incisor retraction. Archwire was not reactivated for about 10 weeks.

Finished occlusion, showing excellent anchorage control, overbite correction, and anterior incisor angulation.

Presented by:

Dr. Ahmed Saeed Baattiah

E-mail :[email protected]

re REFERENCES

ORTHODONTICS CURRENT PRINCIPLES AND TECHNIQUES 5TH EDITION (GRABER ).

CONTEMPORARY ORTHODONTICS (WILLIAM R.PROFFIT )

SCIENCE DIRECT DATABASE

TEXTBOOK OF ORTHODONTICS ( SAMIR BISHARA )

HANDBOOK OF ORTHODONTICS (ROBERT MOYERS )

class ii div 2 malocclusion

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