& its management in stage i of

8/14/2019 & Its Management in Stage I Of

1/89

Anchorage

&Its Management In

Stage I Of Begg


2/89

Anchorage

Webster a secure hold sufficient toresist a heavy pull

In orthodontics nature and degree ofresistance to unwanted displacementoffered by an anatomic unit, when usedfor purpose of effective toothmovement


3/89

Anchorage management

Involves restricting movement of onegroup of teeth while facilitatingmovement of other teeth.

Successful anchorage management iskey to successful orthodontictreatment.


4/89

Anchorage preparation is mostimportant step in clinical orthodontics

(Tweed)

Begg light wire appliance develops itstotal anchorage potential from with inthe mouth.


5/89


6/89

A threshold, below which pressure would

produce no reaction perfect anchorage

control since it would only be necessary to be

certain that the threshold for tooth

movement was not reached for teeth in

anchorage unit.


7/89


8/89

Optimum orthodontic force level for

movement is the lightest force &

resulting pressure that produces anear maximum response

Force > that ,equally effective butwould be unness. traumatic & stressful

to anchorage


9/89

Anchorage situations

Reciprocal anchorageforce applied

to teeth & to arch segments areequal ,so the force distribution in

PDL


10/89

Anchorage value

Anchorage value of any tooth

roughly eq. to its root surface area

5 & 6 in each arch is appro. eq. in

surface area to 1,2 & 3

Freemansanchorage valuediagram


11/89

Reinforced anchorage

By adding more resistance units.

It is effective because with more

teeth (extraoral structures) in the

anchorage, reaction force distributed

over a larger PDL area.


12/89

Stationary anchorage

Bodily movement of one group of

teeth against tipping of others


13/89

Anchorage bend

In beggs technique anchorage is

used

For retraction and intrusion

Derived from single bend (anchorage

bend)


14/89

Anchorage bend

Formerly called the tip-back bend.

Bend whose vertex faces occlusally

Placed in buccal segment at some point

mesial to the tube.


15/89

The manner in which anchorage isobtained for vertical movements-

When initial arch wire is inserted the AB ant. Portion should rest inmucobuccal fold

Engaged in brackets

wire will exert force on molar, occlusal

pressure on mesial end of tube and gingival

pressure on distal end


16/89


17/89

These tendencies encounter certainresistance

Ex. Of mesial cusp opp. Occl. Force

Int. of distal cusp bone

Distal tipping of crown 2nd & 3rd molars

Mesial tipping of root bone on mesial surface

Resistance not equal magnitude prevent effect of

anchorage bend


18/89

If arch wire viewed from side, mildlygingival curve

reflect force for overbite correction

resistance to movement exhibited by molar

The amount of constant light force,

optimal for intruding the anterior

at a minimal level to produce movement

of molars.


19/89

The manner in which anchorage isobtained for retraction

After arch wire attached

class II elastic between I.M.H of upper arch

wire & hook on mesial end of lower molar

tube.

Tend to pull molar forward & retractanteriors


20/89

AB counteract mesial pull

If appro. Ab and elastics are used

(proper m/f) tooth lean upright,& if

move, bodily


21/89

At the same time e retract ant. Ling. by

tipping

The amount of force exerted by elastic

Optimal for tip the anterior backwards

At a minimal level to move of molars

forward bodily.


22/89

Amount of force exerted by wire &

elastics is important if desired

movements are to be attained with

minimal anchorage loss, throughout

the Rx.


23/89

Orthodontic Judo

Based on using the opponents greater

strength and weight to his disadvantage

Enable a weak & small man to overcome

a large & strong man, based on scientific

principles of leverage and balance


24/89

The crown tipping tendency can be used toadvantage

by simply eliminating the stabilizingresistance supplied by wires and

elastics attached to other teeth

crown takes the path of least resistance and

net result crown movement.


25/89

Attainment of beneficial crown tipping

movement resulting from root tipping

force or prevention of detrimental

crown movements by these forces is

called orthodontic judo


26/89

Three elements

Lever arm( arch wire)

Area of High resistance (bone around roots)

Area of low resistance (area around crown)


27/89


28/89

Under certain conditions, and relatively early

in Rx

light forces can induce a backward

movement of anchor molar crown,

which in themselves are being used to move

ant. teeth backward

Contravention to Newtons 3rd law Like lifting yourself off the floor with your

own bootstrap

Operation boot strap: net distal movementof anchor molars with judo mechanics


29/89

AB tends to tip the molar roots

forward and crown backward

Net effect of widespread difference

between the high resistance root

tipping and the low resistance crown

tipping

More crown movement

AB force in first stage & net distalmovement of upper molars


30/89

If molar mesially inclined at comm. of

Rx , net distal movement of crown to

upright position can be sig.for

class II correction

incr. arch length in nonext. Cases.


31/89

For net distal movement

molar crown should freely move back

No binding of arch wire in tube

Do not bend the end of arch wire

Do not use tie back ligature to molar

tube


32/89

AB force in first stage with or withoutnet distal movement of lower molars

Lower molar crown also have tendency

to tip back

Controlled by varying the force of class

II elastics

11/2 21/2 ounce (nonext.) crown may

tip back more & root tip forward less


33/89

21/2 31/2 ounce (ext.)both crown & root may tip, uprighting

the tooth but imparting little or nodistal tipping

Net distal movement is proportional

to amount of elastic force


34/89

The location and degree ofangulations of A.B, depends upon

Types of arch wires

Location of extraction space, if any

Depth of overbite

Hazard of occlusal impingement and distortion aids

Inclination of anchor molars


35/89

Variations in the angulations of AB

Stage of treatment

In stage 1- usually greater than

stage 2 except for open bites

Little if required in stage 3.


36/89

Depth of overbite

In avg. deep bite cases

anterior segment of wire rest passively at thedepth of mucolabial fold

In open bite case-to keep the anchor molar of both jaws upright

against the mesial pull of elastic and wire. After OBcorrection

to prevent dev. excessive OB or distal tipping of

molars.


37/89

Rate of progress of case If progress is unsatisfactory, bend or

relocate bend closer to molar tube.

Inclination of anchor molar at thecommencement of the treatment

If molars are inclined mesially AB, so

that wire rests passively in mucolabialfold.


38/89

On severe mesial inclination-

No AB initially

Later for uprighting molar

unilaterally mesial inclined molar

the increased intrusive force on that

side can be prevented by using vertical

elastics and arch wires.


39/89

Variation in location of AB

Stage 1 of treatment

placed forward to the molar tooth to

permit it to slide back to tube during

space closer

but not to enter the tube


40/89

At the commencement of treatment

distal to premolar or tip of buccal cusp

Mild overbite/open bite cases

formed as gentle curve located at the head of

bicuspid bracket


41/89

Nearer to molar tube

Occlusal impingement

Difficulty and delay in overbite

correction

non extraction case

In first molar extraction cases In second bicuspid extraction cases


42/89

When progress rapid

placed farther forward

If little space remains

placed far enough forward to

assure that old teeth will come intoproximal contact before AB reach themolar tube.

The rate of progress and amount ofspace remaining


43/89

Location of AB in loop archwires

used for 2-3 appointments

placed far enough forward to assure that

it will not slide back and reach the molar tube.


44/89

Causes of loss

of Anchorage in stage I

and

its prevention


45/89

Vertical loop touching the labialsurface of the teeth

A loop resting but not touching labial

surface of ant. teeth

As the crown tip lingually loop is moved

towards the teeth inhibit further free

tipping of ant. Teeth in same arch, may

affect opp. Arch also.


46/89

Prevention

Proper arch wire fabrication

Proper location of loops & limitation of the

number of loops

Slightly labial inclination of loops in severe

crowding cases


47/89

Vertical loop impinging on thegingival tissue

Prevent free tipping but less than if

touching the tooth

If impinge on gingiva become imbedded

by next visit

Prolong first stage I


48/89

Prevention

Care modification of loops

Slightly labial inclination of loops when arch

first applied

Do not modify the loop without removing

from mouth


49/89

Intermaxillary hooks not crankedout

Vertical portion of I.M.H resting snugly

against the canine +ve braking

mechanism

Prevention

I.M.H should be cranked out before arch wire

is applied

Use horizontal circle

Distal leg of I.M.H sliding against the


50/89

Distal leg of I.M.H sliding against thelock pin & becoming engaged in caninebracket

Prevents free and simple tipping of canine

crown

Usually happen when loop arch wire are used

to unravel ant. Crowding


51/89

Prevention

I.M.H should be cranked far enough

labillay, engage against the mesial

surface of bracket



52/89

Elastic over the I.M.H engaging thelabial surface of canine

Not major cause

Due to using thick elastics or two elastics

Prevention Modify I.M.H so that elastic not

produce undesirable pressure


k b d h h


53/89

Lock pin binding the arch wirein the bracket

If one or more ant. teeth are bind

Prevention Use special safety lock pins

If conv. Pins, tails should be bend

before head strike the arch wire


54/89

Cuspid forced out into buccal plate

Improper arch wire form

Causes drag teeth can not tip freely

P ti


55/89

Prevention

Place the distal ends of arch wire in

molar tubes, see if wire lies so far

labially in canine region


56/89

Too strong elastic force

Use proper intermaxillary elasticforce

2-21/2 ounce

Molar will come forward


57/89

Wearing more than one elastic

Pt. must be properly educated in

function of elastics

Danger of wearing more elastics


58/89

Elastics not worn continuously

Intermittent wearing causes anchor tooth

to become loose

Ant. Teeth hardly move Prolong Rx anchorage loss

Prevention

Proper patient education

A h i id t ll d i


59/89

Arch wire accidentally engaged inthe slot of second premolar

Increases friction

In mes.ling molar rotation wire may acci.

engage

Prevention Use of bypass clamp

Remove the premolar band for first 6 weeks


60/89

Arch wire binding in buccal tube

If arch wire too short to protrude through the

distal end of molar tube

When cut to proper length, cause internal

burring (not removed by ordinary polishing)

Prevention Make always slightly longer than necessary

Do not cut the end of wire until allmodifications and bends, 1/8should protrude

E d f h i t iki th


61/89

End of arch wires striking thesecond permanent molar

Retards and sometimes stops the

distal sliding of arch wire (usually in

upper molar)

Prevention


62/89

Prevention

Extend the arch wire farther distally

through the 1 molar tube not only to

prevent striking but also to move 2nd molar lingually

If impossible, cut it short enough to

allow it to slide freely until next visit


63/89

End of arch wire penetrating thegingival tissue

Usually distal end of lower arch

Gingival tissue (bone) prevent freesliding

Prevention Patients should be instructed to visit

orthodontist if they feel discomfort orCan not engage elastics


64/89

Anchorage bends engaging buccaltube

Once entered in molar tube free slidingis prevented due to three point contact

Prevention Check the situation every visit If necessary remove the

arch wire, st. it and, makenew anchor bend mesially


65/89

Ligating premolar too tightly toarch wire

Arch wire can not slide distally

Prevention Ligate the arch wire lightly so that arch

is free to slide

ff h b d f


66/89

Insufficient anchorage bend in firstarch wire when first applied

Good rule to follow to incorporate

enough AB to cause the ant. section to

lie against the floor of mucobuccal fold

when distal ends of arch wire is

threaded into molar tubes.

P i


67/89

Prevention

Not to estimate the amount of bend in

number of degrees, because

Inclination of molar and buccal tube

Length of arch wire

must be taken into account


68/89

Distorted anchorage bend

Seen in negligent pt. mesial to lowermolar tube, esp. when lower 2ndpremolars are not present

Prevention Examine the arch wire closely

If distorted ,remove from mouth,eliminate the distortion

T h h b d


69/89

Too much anchorage bend

May cause distortion of arch wire

May cause arch wire to rotate in molartubes rotate the molars failing todepress molars


70/89

Improper toe in

Results in loss of control of anchor teeth &

failure to reduce ant. Deep bite.

Proper amount of toe in or toe out is

determined by placing the arch wire in molar

tubes & in anterior brackets

The wire should pass st. forward and occlusally

as it leaves the tube from the action of

anchorage bend.


71/89

Arch wire too soft

Arch wire material must have higherresiliency that is compatible withfreedom from likelihood of # of arch

wire while they are being worn

Other wise Rx time will increase

more anchorage loss

O ti t d i l


72/89

Overactivated expansion loops orimproperly bent arch wires

Cause rapid initial labial tipping and

spacing of ant. Teeth

More force time spend to recover

original lab.ling.

inclination of ant. Teeth

Loss of anchorage

B d f d f l k i


73/89

Bend over free end of lock pinimpinging on arch wire

A lock pin tail striking the wire distal tocaninedoes more harm than the samein C.I

Prevention Use short lock pin or cut the lock pin

tail off flush with the side of bracket

Bend all pins tail to mesial.


74/89

Wrong type of bracket

Do not edge wise bracket

May allow ample tipping labiolingually

but it restricts mesiodistal tipping and

causes loss of anchorage

A h i lli i b l t b


75/89

Arch wire rolling in buccal tube

Avoid too much anchorage bend

and/or too much toe in bend


76/89

Improper arch wire form

Arch wire should keep all teeth in thecancellous through of alveolar bone

Arch wire must be bilaterally similarin form or should be so shaped as toeliminate any asymmetry of arch

Upper and lower arch wire forms


77/89

Upper and lower arch wire formsnot coordinated

Teeth will assume faulty relationship

Ant. or pos. cross bite cuspal

interference prolonged Rx time

Internal diameter of buccal tube


78/89

Internal diameter of buccal tubetoo small or large

Best internal diameter 0.036 for 0.016

wire

if less free sliding will reduced

if more molar control lessen,

depression force on ant. Lessen


79/89

length

Length 0.20 0.25,

shorter tube lessens molar control &force of anchor bend,

longer tube more control, reduces the

distance of arch wire between mesialend of molar tube and premolar bracketoperational difficulties during stage 3.

Retaining looped arch wire longer


80/89

Retaining looped arch wire longerthan necessary

Danger of loops moving into suchpositions that they press againstlabial surface of ant. teeth

Not transmit tooth depressing forceas accurately as an arch wire withoutloop

Cuspid will depress more thanincisors

Binding of doubled back arch wire


81/89

Binding of doubled-back arch wirein flat oval tube

Binding will occur by having the legs too

far apart

May be due to too large a radius wherethe arch wire returned on itself, or too

long a vertical section extending from the

hook that is wound around the arch.

Legs of double back are not ll.

Curving arch wires between


82/89

Curving arch wires betweenexpansion loops

Make the arch wire st. between the loops

If need to modify the form make bends in

the loops

When engaged, loops become distorted

rotations of the sections of archwire

If curved three point contact inhibit free

lab.ling. tipping

Thumb or finger sucking lip sucking tongue


83/89

Thumb or finger sucking, lip sucking,tonguethrusting and abnormal sleeping habits

Retard or prevent treatment progress

Cause loss of anchorage

Prevention

Habit breaking measures


84/89

Improper ligature tie at canine

do not pass ligature ties on caninesover the incisal of brackets prevents free tipping

It should pass directlydistally across the labial

surface of canine


85/89

Anchorage bend too far mesially

Ideal location at the mesial of anchor molar

It may become restricted by ligature tie on

bicuspid, preventing free distal sliding Arch wire will be projected towards

the occlusal plane

and be deformed by occlusal

forces.


86/89

prevention

Anchorage curves instead of bends

Gently curved anchor bend can be

initially placed so far mesially in the arch

wire that it is unnecessary to remove the

arch wire from mouth in order to make a

new bend farther.


87/89

Using 0.014 instead of0.016 wire

0.014 exerts insufficient force from

its anchorage bend to prevent the

anchor molars from being tipped

mesially.

Ant. Deep bite will also not open


88/89

Loosening of anchor molar bend

Pull the affected molar forward

Anterior teeth are not depressed


89/89

Conclusion

Place adequate anchorage bends in

both arch mesial to molar tubes

Use of arch wires, rubber elastics

which exert tooth moving forces of

low value.

Not to move any teeth bodily other

than anchor molars in stage I

& its management in stage i of

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