Dfo

www.indiandentalacademy.comwww.indiandentalacademy.com

ContentsContents
– IntroductionIntroduction
– History Of Extraoral Orthopedic ApplianceHistory Of Extraoral Orthopedic Appliance
– Orthodontic and Orthopedic ForcesOrthodontic and Orthopedic Forces
– Key to Understanding the Extraoral ForcesKey to Understanding the Extraoral Forces
– HeadgearHeadgear
CervicalCervical
OccipitalOccipital
Combi-pullCombi-pull
Vertical pullVertical pull
OthersOthers
– Maxillary splint - Headgear CombinationMaxillary splint - Headgear Combination
– Activator - Headgear CombinationActivator - Headgear Combination
– Frankel - Headgear CombinationFrankel - Headgear Combination

 Facial MaskFacial Mask
 Chin CupChin Cup
 ConclusionConclusion
 ReferencesReferences

INTRODUCTIONINTRODUCTION
 The term orthopedics derives fromThe term orthopedics derives from
Greek and literally means “properGreek and literally means “proper
education”. Consequently theeducation”. Consequently the
fundamental principle of orofacialfundamental principle of orofacial
orthopedics is to aim at optimizingorthopedics is to aim at optimizing
the development of the structuresthe development of the structures
i.e., to remove restrictions ori.e., to remove restrictions or
retardation’s in the accomplishmentretardation’s in the accomplishment
of growth patternof growth pattern

 The broader description of “dentofacialThe broader description of “dentofacial
orthopedics” conveys the concept thatorthopedics” conveys the concept that
treatment aims to improve not onlytreatment aims to improve not only
dental and orthopedic relationships indental and orthopedic relationships in
the stomatognathic system but alsothe stomatognathic system but also
facial balance.facial balance.

 Ideally dentofacial orthopedic includesIdeally dentofacial orthopedic includes
those appliance that are classifiedthose appliance that are classified
under functional jaw orthopedics, itunder functional jaw orthopedics, it
would be more appropriate to discusswould be more appropriate to discuss
those appliance that have their effectsthose appliance that have their effects
or action primarily targeted towardsor action primarily targeted towards
the skeletal tissue rather than the softthe skeletal tissue rather than the soft
tissue therefore the seminar is limitedtissue therefore the seminar is limited
to extraoral orthopedic appliance liketo extraoral orthopedic appliance like
head gear, facial mask & chin cup.head gear, facial mask & chin cup.

HISTORY OF EXTRAORALHISTORY OF EXTRAORAL
ORTHOPEDIC APPLIANCEORTHOPEDIC APPLIANCE
 An extraoral appliance in the form ofAn extraoral appliance in the form of
a skull cap in combination with a china skull cap in combination with a chin
cup, was used in the earlycup, was used in the early
nineteenth centurynineteenth century
 . The chin cup was used by Cellier in. The chin cup was used by Cellier in
1802 and a year latter by Fox as a1802 and a year latter by Fox as a
occipital anchorage in cases ofoccipital anchorage in cases of
luxation and not for occipitalluxation and not for occipital
anchorage as of today.anchorage as of today.

Chin-cap devised by Fox, 1803 used as
an occipital mental sling for luxation
Chin-cap devised by Cellier, 1802,
though not used for occipital
resistant

Gunnel first wrote on the use ofGunnel first wrote on the use of
headgear for occipital anchorageheadgear for occipital anchorage
in 1822 - 1823.in 1822 - 1823.
Kneissel (1863) published a reportKneissel (1863) published a report
on the headgear or occipitalon the headgear or occipital
anchorage for the correction ofanchorage for the correction of
mandibular protrusion.mandibular protrusion.

Guilford {1866} used theGuilford {1866} used the
headgear for reducingheadgear for reducing
protruding mandibles as forprotruding mandibles as for
correcting protrudingcorrecting protruding
maxillary incisor teeth .maxillary incisor teeth .
Schange {1884}wrote on theSchange {1884}wrote on the
use of headgear.use of headgear.

 In 1892 Kingsley described a techniqueIn 1892 Kingsley described a technique
for driving maxillary teeth distally byfor driving maxillary teeth distally by
means of a headgear withoutmeans of a headgear without
extracting teeth . This headgearextracting teeth . This headgear
consisted of a cloth covering the backconsisted of a cloth covering the back
and top of head & the pulling force wasand top of head & the pulling force was
transmitted by elastic.transmitted by elastic.

Angle advocated the head cap forAngle advocated the head cap for
growth modification of maxilla,growth modification of maxilla,
retraction & intrusion of maxillaryretraction & intrusion of maxillary
anteriors.anteriors.

Case in the early 1900s usedCase in the early 1900s used
extra oral anchorageextra oral anchorage
extensively in the treatment ofextensively in the treatment of
blocked-out canines.blocked-out canines.
11stst
half of 20th century-half of 20th century-
decreasedecrease extraoral traction ,extraoral traction ,
because : intrermaxillarybecause : intrermaxillary
elastics became popular.elastics became popular.

OppenheimOppenheim reintroduced thereintroduced the
extraoral appliances in 1936.extraoral appliances in 1936.
Further modifications to this wereFurther modifications to this were
made by Farrar, Goddard, Angle,made by Farrar, Goddard, Angle,
Maccoy, Jackson,Maccoy, Jackson, KloehnKloehn andand
othersothers Headgear as used by
Farrar (1836)
Angle orthod 1936;6:153-183Angle orthod 1936;6:153-183
Angle Orthod 1947;17:10-23Angle Orthod 1947;17:10-23www.indiandentalacademy.comwww.indiandentalacademy.com

 orthodontic forces thatorthodontic forces that
moves teeth efficientlymoves teeth efficiently
 applied to the teeth byapplied to the teeth by
means of wires andmeans of wires and
active components ofactive components of
the removable or fixedthe removable or fixed
applianceappliance
 The force produced byThe force produced by
these appliances arethese appliances are
light and range fromlight and range from
50 – 100gms50 – 100gms
 orthopedic force thatorthopedic force that
affects the deeperaffects the deeper
craniofacial structurescraniofacial structures
 Applied toApplied to
nasomaxillary complexnasomaxillary complex
or mandible byor mandible by
various appliancesvarious appliances
 The orthopedic forceThe orthopedic force
on the other hand areon the other hand are
heavy forces of overheavy forces of over
400gms.400gms.
ORTHODONTICS ANDORTHODONTICS AND
ORTHOPEDICS FORCESORTHOPEDICS FORCES

 According to ProfitAccording to Profit
Characteristics to produce skeletalCharacteristics to produce skeletal
versus dental changes.versus dental changes.
Dental ChangesDental Changes SkeletalSkeletal
ChangesChanges
Force magnitudeForce magnitude :Low:Low HighHigh
Force directionForce direction :Any:Any Not extrusiveNot extrusive
Treatment timeTreatment time :Varies:Varies Long.Long.
Rate of change :1 mm/month max.Rate of change :1 mm/month max. 3-4mm/years max.3-4mm/years max.
The direction and duration of the force are as significant asThe direction and duration of the force are as significant as
the amount of force appliedthe amount of force applied

 Graber advocates a force applicationGraber advocates a force application
of more than 400gm for 10-12 hours /of more than 400gm for 10-12 hours /
day - body to restore, for healingday - body to restore, for healing
purpose.purpose.

The recommended extraoral force levelThe recommended extraoral force level
/side(gm):/side(gm):
 Full mixed dentition- 250 to 300.Full mixed dentition- 250 to 300.
 Mixed dentition during exfoliationMixed dentition during exfoliation
-150 to 250.-150 to 250.
 Full permanent dentition-400 to 500.Full permanent dentition-400 to 500.
 Retention in full permanent dentitionRetention in full permanent dentition
-150 to 400-150 to 400

EXTRAORAL ORTHOPEDICEXTRAORAL ORTHOPEDIC
APPLIANCESAPPLIANCES
 HEADGEARHEADGEAR
 FACIAL MASKFACIAL MASK
 CHINCUPCHINCUP

HEAD GEARHEAD GEAR
 Head gears are the most commonlyHead gears are the most commonly
used extraoral orthopedic appliances.used extraoral orthopedic appliances.
They are used during the growthThey are used during the growth
period to intercept or correct certainperiod to intercept or correct certain
skeletal malocclusions as well as toskeletal malocclusions as well as to
distalize the maxillary dentition ordistalize the maxillary dentition or
maxilla itself. Head gears also formmaxilla itself. Head gears also form
one of the important adjuncts toone of the important adjuncts to
control or gain anchorage.control or gain anchorage.

HISTORICAL PERSPECTIVEHISTORICAL PERSPECTIVE
Use of extraoral forces to modifyUse of extraoral forces to modify
the growth of the maxilla has a longthe growth of the maxilla has a long
history, dating back to Kingsley andhistory, dating back to Kingsley and
Angle in the 19th century. Both usedAngle in the 19th century. Both used
occipital headgears to retract andoccipital headgears to retract and
intrude maxillary incisors.intrude maxillary incisors.

Interest in extraoral tractionInterest in extraoral traction
diminished in the first half of thediminished in the first half of the
20th century, especially with the20th century, especially with the
increased popularity of intermaxillaryincreased popularity of intermaxillary
elastics.elastics. Interest in headgear wasInterest in headgear was
revived by Oppenheim & later byrevived by Oppenheim & later by
Kloehn who recommended theKloehn who recommended the
application of extra-oral forces forapplication of extra-oral forces for
the mass distal movement of teeththe mass distal movement of teeth

Components of HeadgearComponents of Headgear
The head gear - face bow assemblyThe head gear - face bow assembly
has three main componentshas three main components
 11.. Face bowFace bow
 2. The force element2. The force element
 3. The head cap or cervical strap3. The head cap or cervical strap

Face bowFace bow
 The face bow is aThe face bow is a
metallic componentmetallic component
that helps inthat helps in
transmitting thetransmitting the
extra-oral forcesextra-oral forces
on to the posterioron to the posterior
teeth. The faceteeth. The face
bow consists ofbow consists of
outer bow, innerouter bow, inner
bow and thebow and the
junction .junction .
Fig.1. Facebow (A) Outer bow (B)
Inner bow (C) Junction

Types of facebowTypes of facebow
two types of facebows can be usedtwo types of facebows can be used
 Inner-outer bow typeInner-outer bow type
 J-hook typeJ-hook type
-bows, Inner-outer bow type (left) and J-hook type (right)

According to origin of forceAccording to origin of force
facebow divided into as followsfacebow divided into as follows
 Cervical-pullCervical-pull
facebowfacebow
 High-pull facebowHigh-pull facebow
 Combi facebowCombi facebow
 AsymmetricAsymmetric
facebowfacebow

Bending of Facebow:Bending of Facebow:

Placement of Facebow:Placement of Facebow:
 In a correctly fitted appliance, theIn a correctly fitted appliance, the
soldered joint should comfortablysoldered joint should comfortably
placed between the lips. When theplaced between the lips. When the
elastic strap is put on the outer bowelastic strap is put on the outer bow
should not stick into the patientsshould not stick into the patients
cheeks. The inner bow should fitcheeks. The inner bow should fit
passively into the headgear tubes ifpassively into the headgear tubes if
it does not there will be looseit does not there will be loose
bandsbands

 Buccal tubesBuccal tubes are positioned eitherare positioned either
gingivally or occlusally on the molar bracket.gingivally or occlusally on the molar bracket.
 The outer bowThe outer bow ends anteriorly to the earsends anteriorly to the ears
and should be 5 to 10mm from the cheeks.and should be 5 to 10mm from the cheeks.
 Adjustments to the outer bow can be madeAdjustments to the outer bow can be made
in six directions: bucco-lingually, superior-in six directions: bucco-lingually, superior-
inferiorly, and antero-posteriorly.inferiorly, and antero-posteriorly.

 Inner bow;Inner bow; Proper adjustment of the innerProper adjustment of the inner
bow will allow the wire to slide in and out ofbow will allow the wire to slide in and out of
the headgear tubes easily when the posteriorthe headgear tubes easily when the posterior
strap is not attached.strap is not attached.
 The bow should be in a passive positionThe bow should be in a passive position
between the two lipsbetween the two lips

The force element:The force element:
It is that part of the assemblyIt is that part of the assembly
which provides the force to bringwhich provides the force to bring
about the desired effect. This mayabout the desired effect. This may
comprise of springs, elastics andcomprise of springs, elastics and
other stretchable materials. Theother stretchable materials. The
force element connects the faceforce element connects the face
bow to the head cap or neckbow to the head cap or neck
strap.strap.

The head cap or cervical strap:The head cap or cervical strap:
The appliance takes anchorage from theThe appliance takes anchorage from the
rigid bones of the skull or from the back ofrigid bones of the skull or from the back of
the neck by means of a head cap or neckthe neck by means of a head cap or neck
strap or a combination of the two. Thestrap or a combination of the two. The
selection of this depends upon the individualselection of this depends upon the individual
patient needs.patient needs.

Based on the site ofBased on the site of
anchorage, the head gearsanchorage, the head gears
can be of three types :can be of three types :
 Cervical head gearsCervical head gears
 Occipital head gearsOccipital head gears
 Combination head gearsCombination head gears
JCO 1982 MAY 308-312JCO 1982 MAY 308-312

Cervical head gears (Low pullCervical head gears (Low pull
head gear)head gear)

Occipital head gears (HighOccipital head gears (High
pull head gear)pull head gear)

Combination head gearsCombination head gears
(Medium pull head gear)(Medium pull head gear)

Vertical-Pull HeadgearVertical-Pull Headgear

Other typesOther types
 Interlandi Type:Interlandi Type:
(no failsafe(no failsafe
mechanism)mechanism)
 AsymmetricAsymmetric
Headgear:Headgear:

Selection of Headgear TypeSelection of Headgear Type
There are three major decisions to beThere are three major decisions to be
made in the selection of headgear.made in the selection of headgear.
1)1) The headgear anchorage locationThe headgear anchorage location
2) How the headgear is to be2) How the headgear is to be
attached to the dentitionattached to the dentition
3) whether bodily movement or3) whether bodily movement or
rotation of maxilla is desired.rotation of maxilla is desired.

A KEY TO UNDERSTANDING OFA KEY TO UNDERSTANDING OF
EXTRAORAL FORCESEXTRAORAL FORCES
The mechanical principles that needThe mechanical principles that need
to be defined include the following:to be defined include the following:
 ForceForce
 Force resolutionForce resolution
 Center of resistanceCenter of resistance
 Center of rotationCenter of rotation
 Line of actionLine of action

ForceForce
 A force is that which changes orA force is that which changes or
tends to change the position of resttends to change the position of rest
of a body or its uniform motion in aof a body or its uniform motion in a
straight line.straight line.

Force resolutionForce resolution
 Forces may be resolved intoForces may be resolved into
component vectors which, in a singlecomponent vectors which, in a single
plane of space, are at right angles toplane of space, are at right angles to
each other.each other.

Components of a force/ Force resolutionForce resolution
F
F cos ø
F sin ø
ø

The resultant of 2 force with different point of application
can be determined by extending the line of action to
construct a common point of application

Line of actionLine of action
 line of action of aline of action of a
force is that lineforce is that line
connecting the pointconnecting the point
of origin of the forceof origin of the force
(head – or neckgear(head – or neckgear
assembly hook) toassembly hook) to
the point ofthe point of
attachment (hook)attachment (hook)
on the outer bow.on the outer bow.

Center of resistanceCenter of resistance
Center of massCenter of mass of aof a free bodyfree body is the pointis the point
through which an applied force must pass tothrough which an applied force must pass to
move it linearly without any rotation. This centermove it linearly without any rotation. This center
of mass is the free objects “Balance Point”of mass is the free objects “Balance Point”
TheThe center of resistancecenter of resistance is the equivalentis the equivalent
balance point of abalance point of a restrained bodyrestrained body..
 By definition , a force with a line of action passingBy definition , a force with a line of action passing
throughthrough center of resistancecenter of resistance producesproduces translationtranslation

Center of rotationCenter of rotation
 The center of rotation of a body is aThe center of rotation of a body is a
point around which the body willpoint around which the body will
rotate or tip.rotate or tip.
OROR
 Center of rotation is a point , aboutCenter of rotation is a point , about
which a body appears to havewhich a body appears to have
rotated , as determined form itsrotated , as determined form its
initial and final positionsinitial and final positions

 The center of resistance of the bodyThe center of resistance of the body
(tooth/maxilla/mandible) remains(tooth/maxilla/mandible) remains
constant.constant.
 The variables are, thereforeThe variables are, therefore
a) the distance of the line of actiona) the distance of the line of action
from the center of resistance and,from the center of resistance and,
b) the inclination (or steepness) of theb) the inclination (or steepness) of the
line of action.line of action.
Clinical Application of AboveClinical Application of Above
PrinciplesPrinciples

CresD
Distance of the line of actionDistance of the line of action
from the center of resistance.from the center of resistance.

The inclination of the line of actionThe inclination of the line of action
 The inclination or steepness of theThe inclination or steepness of the
line of action can be varied and isline of action can be varied and is
dependent upon (1) The point ofdependent upon (1) The point of
origin of the force andorigin of the force and
(2) The point of attachment of the(2) The point of attachment of the
force.force.

 TheThe point of originpoint of origin ofof
the force isthe force is
dependent upon thedependent upon the
type of assemblytype of assembly
that is used. Thethat is used. The
numerous extraoralnumerous extraoral
assemblies availableassemblies available
may be groupedmay be grouped
conveniently intoconveniently into
three majorthree major
categoriescategories
P. Parietal, O. Occipital, C. Cervical

 TheThe point ofpoint of
attachmentattachment of theof the
force is the hookforce is the hook
on the outer bowon the outer bow
of the extraoralof the extraoral
assembly.assembly.

 The shape of the outer bow is of noThe shape of the outer bow is of no
consequence and has no effect on theconsequence and has no effect on the
application of force to molar teeth,application of force to molar teeth,
provided the relationship of the pointprovided the relationship of the point
of attachment (outer bow hook) to theof attachment (outer bow hook) to the
site of origin of the force remainssite of origin of the force remains
unaltered, namely, D1 = D2. Thisunaltered, namely, D1 = D2. This
contention applies only if it assumedcontention applies only if it assumed
that the arms of the headgear arethat the arms of the headgear are
rigid.rigid.

 The points of attachment of the outerThe points of attachment of the outer
bow hooks are variable and may bebow hooks are variable and may be
altered to fit anywherealtered to fit anywhere
1) varying the length of the outer1) varying the length of the outer
bow,bow,
2) varying the angle between the2) varying the angle between the
inner and outer bows, andinner and outer bows, and
3) varying the length and the angle of3) varying the length and the angle of
the outer bow.the outer bow.

AJO DO 90: 29-36, 1986
J Biomed Eng10(3);246-252,1988
BJO VOL 22/1995/227-232

JCO 1982 MAY 308-312JCO 1982 MAY 308-312
Effects ofEffects of
Cervical headCervical head
gearsgears

Effects ofEffects of Cervical head gearsCervical head gears
 Cervical pull force vector inferior toCervical pull force vector inferior to
both centers of resistanceboth centers of resistance

 Cervical pull force vector passingCervical pull force vector passing
between the centers of resistancebetween the centers of resistance

 If cervical head gear force to the maxillaIf cervical head gear force to the maxilla
moves it downward, mandibular growth willmoves it downward, mandibular growth will
be expressed more vertically and lessbe expressed more vertically and less
horizontally, impeding the successfulhorizontally, impeding the successful
correction of a Class II problem.correction of a Class II problem.

JCO 1982 MAY 308-312JCO 1982 MAY 308-312
Effects ofEffects of
occipital headoccipital head
gearsgears

Effects ofEffects of occipital headoccipital head
gearsgears
 occipital pull force vector inferior tooccipital pull force vector inferior to
both centers of resistanceboth centers of resistance

 occipital pull force vector passingoccipital pull force vector passing
between the centers of resistancebetween the centers of resistance

Effects ofEffects of Straight-Straight-
PullPull HeadgearHeadgear
JCO 1982 MAY 308-312JCO 1982 MAY 308-312

Effects ofEffects of Vertical-Vertical-
Pull HeadgearPull Headgear
JCO 1982 MAY 308-312JCO 1982 MAY 308-312

Clinical Application of Head GearClinical Application of Head Gear
 There are four main uses ofThere are four main uses of
headgear force in contemporaryheadgear force in contemporary
treatment of Class II malocclusions:treatment of Class II malocclusions:
1. Anchorage control.1. Anchorage control.
2. Tooth movement.2. Tooth movement.
3. Orthopedic changes.3. Orthopedic changes.
4. Controlling the cant of the occlusal4. Controlling the cant of the occlusal
plane.plane.

 The majority of authors believe thatThe majority of authors believe that
the amount of force applied to maxillathe amount of force applied to maxilla
by extra oral traction should lieby extra oral traction should lie
between 400-800gmbetween 400-800gm
 Graber advocates a force applicationGraber advocates a force application
of more than 400gm for only 10 – 12of more than 400gm for only 10 – 12
hours/day to produce significant basalhours/day to produce significant basal
bone effects and to allow the body tobone effects and to allow the body to
restore normal circulation to therestore normal circulation to the
periodontium for healing purpose.periodontium for healing purpose.

►Preadolscent patient- 12hrs each nightPreadolscent patient- 12hrs each night
►Adolscent patients- at least 14 hrs eachAdolscent patients- at least 14 hrs each
nightnight
(Total magnitude of the growth is not(Total magnitude of the growth is not
changed but its direction)changed but its direction)
Nanda et alNanda et al

Treatment TimingTreatment Timing
 Orthopedics has shown us thatOrthopedics has shown us that
pressure on bone causes it topressure on bone causes it to
change.change.
 Pressure on growing bone has evenPressure on growing bone has even
more dramatic results.more dramatic results.
 Thus, to effect maximumThus, to effect maximum
morphologic changes in bone,morphologic changes in bone,
pressure should be applied during apressure should be applied during a
period of rapid growth.period of rapid growth.

 Woodside was able to demonstrateWoodside was able to demonstrate
three possible periods of acceleratedthree possible periods of accelerated
growth.growth.
The peak period in boys are judged toThe peak period in boys are judged to
be 6½yrs , 9yrs and 15yrsbe 6½yrs , 9yrs and 15yrs
and girls 6yrs. 7½yrs and 12yrs.and girls 6yrs. 7½yrs and 12yrs.
 Graber: orthopedic guidance potentialGraber: orthopedic guidance potential
exists from birth to 12 – 13yrs in girlsexists from birth to 12 – 13yrs in girls
and almost 18yrs in boys.and almost 18yrs in boys.

Safety MeasuresSafety Measures
 Of major concern to orthodontistsOf major concern to orthodontists
everywhere have been a few injurieseverywhere have been a few injuries
from extra oral appliances that couldfrom extra oral appliances that could
have been avoided with proper carehave been avoided with proper care
 The majority of incidence seems toThe majority of incidence seems to
occur from accidentaloccur from accidental
disengagement.disengagement.

Orthodontic facebows: safety issues and current
management
R. H. A. Samuels and N. Brezniak
Self-releasing mechanisms have been incorporated in traction devices to
prevent or reduce the catapult effect. The travel provided by the new models
should permit a comfortable range of head movement by the patient without
unintentional release. The minimum strap extension required for high-pull
headgear is about 10mm, and 25 mm is required for the neck-strap. This
should allow enough extension to attach the strap to the outer hook of the
facebow.
Shielded facebows might reduce the severity of some traumas, but they
are not self-retentive. The authors elected to use the Niton locking facebow.
According to the authors, if a patient removes the extraoral traction and
facebow during sleep and leaves it in the bed and cannot remember doing
this on more than 2 occasions, he or she should discontinue it.
These proactive suggestions should help improve patient safety, increase
the hours of wear, and support the continued use of a very useful piece of
orthodontic equipment.

 Unfortunately, no method can confirmUnfortunately, no method can confirm
absolute safety, but because Headabsolute safety, but because Head
gears are able to cause some injuriesgears are able to cause some injuries
which can have irreversiblewhich can have irreversible
consequences for the clinician it wouldconsequences for the clinician it would
seem wise to use a safety face bowseem wise to use a safety face bow
together a safety release system totogether a safety release system to
improves the safety margin of Headimproves the safety margin of Head
Gears.Gears.

Stress distributions in the
maxillary complex from
headgear forces - three-
dimensional finite element
analysis
For the areas resisting posterior
displacement of the complex,
large normal and shear stresses
were observed in the lower
regions, especially in the
sphenomaxillary and
sphenozygomatic sutures.
The regions resisiting upward
displacement experienced larger
than normal stresses.
The downward force produced
slightly larger stresses than did
the horizontal force and also
varied the nature of stresses
from compressive to tensile or
vice versa in the
temporozygomatic suture.
AO1993;no2:111-118 Tanne K et al

COMPARISON WITH FUNCTIONALCOMPARISON WITH FUNCTIONAL
APPLIANCESAPPLIANCES
► BetweenBetween headgear with splintheadgear with splint VsVs BionatorBionator
► Phase-I - more maxillary skeletal changes in headgear gr & morePhase-I - more maxillary skeletal changes in headgear gr & more
mandibular growth in bionaotrmandibular growth in bionaotr
► Phase-II - Maxillary growth restriction in headgear gr as well asPhase-II - Maxillary growth restriction in headgear gr as well as
mandibular increased growth in bionator gr was lostmandibular increased growth in bionator gr was lost
► Conclusion- Choice of treatment should be based on other factorsConclusion- Choice of treatment should be based on other factors
such as treatment efficiency or a patient’s preference/acceptance ofsuch as treatment efficiency or a patient’s preference/acceptance of
one appliance over the otherone appliance over the other
Chu – Unpublished thesis, Dept ofChu – Unpublished thesis, Dept of
orthodontics, University of Michigan 1997orthodontics, University of Michigan 1997

► Comparison betweenComparison between cervical headgear & FR IIcervical headgear & FR II
► The effect on mid-facial length is less in FR IIThe effect on mid-facial length is less in FR II
► Change in position of point A (3mm) & SNA angel was more in headChange in position of point A (3mm) & SNA angel was more in head
gear grgear gr
McNamara et al Seminar In Orthodontics 1996;2:114-137McNamara et al Seminar In Orthodontics 1996;2:114-137
► The ANB angel decreased 2The ANB angel decreased 200
and mandi plane angel did notand mandi plane angel did not
open.open.
► The treatment effectas are stable 8yrs post treatmentThe treatment effectas are stable 8yrs post treatment
AJODO 1996;109:271-276AJODO 1996;109:271-276
AJODO 1996;109:386-392AJODO 1996;109:386-392

MAXILLARY SPLINT - HEADGEARMAXILLARY SPLINT - HEADGEAR
COMBINATIONCOMBINATION
Appliance EffectsAppliance Effects
 Distal movement of the upper archDistal movement of the upper arch
 Distal tipping of upper molarsDistal tipping of upper molars
 Palatal tipping upper incisorsPalatal tipping upper incisors
 Inhibition of maxillary verticalInhibition of maxillary vertical
development and even intrusion can bedevelopment and even intrusion can be
brought about.brought about.
 Limited clockwise rotation of palateLimited clockwise rotation of palate
occurs.occurs.
 Overbite and especially overjet can beOverbite and especially overjet can be
decreaseddecreased www.indiandentalacademy.comwww.indiandentalacademy.com

Head gear effect
 In functional appliance therapy theIn functional appliance therapy the
mandible is held forward, and themandible is held forward, and the
elastic stretch of soft tissueselastic stretch of soft tissues
produces a reactive effect on theproduces a reactive effect on the
structures that hold it forward . Thestructures that hold it forward . The
soft tissue elasticity creates asoft tissue elasticity creates a
restraining force on the forwardrestraining force on the forward
growth of maxilla called head geargrowth of maxilla called head gear
effect.effect.

Head gear with functional
appliances
 Head gear can be used with all otherHead gear can be used with all other
functional appliances like Activator,functional appliances like Activator,
Bionator, Twin block, FR, Herbst, etcBionator, Twin block, FR, Herbst, etc

 The use of an activator with headThe use of an activator with head
gear was shown by Pfeiffer andgear was shown by Pfeiffer and
Grobety (1972) to reduce theGrobety (1972) to reduce the
duration of treatment significantly.duration of treatment significantly.

Activator - headgear
combination
Orthodontic and orthopedic effects ofOrthodontic and orthopedic effects of
Activator, Activator-HG combination, andActivator, Activator-HG combination, and
Bass appliances: A comparative study.Bass appliances: A comparative study.
( Am J Orthod Dentofac Orthop 1996;110:36-45.)( Am J Orthod Dentofac Orthop 1996;110:36-45.)
 The use of combined activator-high-pullThe use of combined activator-high-pull
head gear appliance has beenhead gear appliance has been
recommended as a means of reducingrecommended as a means of reducing
vertical and sagittal maxillaryvertical and sagittal maxillary
displacement, achieving autorotation, anddisplacement, achieving autorotation, and
increasing forward displacement of theincreasing forward displacement of the
mandible.mandible.

The results of this study led to the followingThe results of this study led to the following
conclusions:conclusions:
 1. Greater improvement in the sagittal1. Greater improvement in the sagittal
skeletal relationship (ANB angle) wasskeletal relationship (ANB angle) was
obtained in both the Bass and ACHG groupsobtained in both the Bass and ACHG groups
than in the Activator group.than in the Activator group.
 2. The Bass appliance was found to be more2. The Bass appliance was found to be more
effective in the control of the unwanted sideeffective in the control of the unwanted side
effects (proclination of the lower incisors,effects (proclination of the lower incisors,
retroclination of the upper incisors).retroclination of the upper incisors).
 3. Unfavorable labial tipping of the lower3. Unfavorable labial tipping of the lower
incisors was prevented also with the ACHGincisors was prevented also with the ACHG
appliance.appliance.

Stability of Class II, Division 1 Treatment with the Headgear-
Activator Combination Followed by the Edgewise Appliance
Guilherme Janson et al
(Angle Orthod 2004;74:594–604.)
The anteroposterior dentoalveolar changes obtained with the
headgear-activator combined appliance, followed by fixed edgewise
appliances, were demonstrated to be stable on a long-term basis.
Sagittal position of both the maxilla and the mandible was stable in
the long term. However, a slight relapse of the maxillomandibular
relation correction occurred, probably
because the maxilla resumed its normal development and the
mandible showed a growth rate significantly smaller than the control
group.

Frankel – head gear combinationFrankel – head gear combination
The modified function regulator appearsThe modified function regulator appears
to offer the following advantages into offer the following advantages in
combining functional jaw orthopedics withcombining functional jaw orthopedics with
directional force headgear in the earlydirectional force headgear in the early
comprehensive treatment of long facecomprehensive treatment of long face
patients: By Allbert H.patients: By Allbert H.
OwenOwen
 1. The vertical dimension or anterior1. The vertical dimension or anterior
facial height (ANS-Me) can be heldfacial height (ANS-Me) can be held
constant or even decreased through theconstant or even decreased through the
holding or intrusion of the upper molars.holding or intrusion of the upper molars.

 2. Although no condylar growth was2. Although no condylar growth was
demonstrable in this study, there isdemonstrable in this study, there is
the potential for increased mandibularthe potential for increased mandibular
growth. It may be limited togrowth. It may be limited to
cooperative patients during growthcooperative patients during growth
spurts.spurts.
 3. There appears to be an3. There appears to be an
improvement in function of the circum-improvement in function of the circum-
and perioral muscles. Upper lipand perioral muscles. Upper lip
integrity appears to be protected inintegrity appears to be protected in
spite of overjet correction or incisorspite of overjet correction or incisor
retraction.retraction.
 4. The significant lateral expansion4. The significant lateral expansion
may reduce the need for extractions.may reduce the need for extractions.www.indiandentalacademy.comwww.indiandentalacademy.com

AO 1980/JAN 54-62AO 1980/JAN 54-62
The apparent backward mandibular
rotation seems to be correlated with
the methods of superimposition, not
the methods of treatment.

A Long-term Study on the Expansion Effects of the Cervical-pull
Facebow With and Without Rapid Maxillary Expansion
J A. McNamara Jr, Baccetti et al
(Angle Orthod 2004;74:439–449.)
• The RME-CFB protocol provided greater net maxillary arch
perimeter increase than did expansion with an inner bow of a
cervical facebow.
• The RME-CFB group had three mm more arch perimeter 10 years
after treatment completion than did the CFB group.
• The stability of expansion achieved with an inner bow of a facebow
was equal to that achieved with a Haas-type RME appliance. Both
expansion protocols retained 90% of the initial intermolar expansion
15 years after expansion.

 Although the facial mask wasAlthough the facial mask was
developed over 100 years ago.developed over 100 years ago.
HickhamHickham claims he was the first toclaims he was the first to
use a reverse headgear. However,use a reverse headgear. However,
this modality was made popular bythis modality was made popular by
DelaireDelaire in late 1960s.in late 1960s.
THE FACIAL MASKTHE FACIAL MASK

 This approach was used infrequentlyThis approach was used infrequently
until reintroduced byuntil reintroduced by DelaireDelaire in the latein the late
1960s for the treatment of cleft1960s for the treatment of cleft
patients.patients.
 Interest in the facial mask in theInterest in the facial mask in the
United States later was stimulated byUnited States later was stimulated by
PetitPetit through his studies conducted atthrough his studies conducted at
Baylor University.Baylor University.

 A reverse pull headA reverse pull head
gear basically consistsgear basically consists
of a rigid extra-oralof a rigid extra-oral
framework whichframework which
takes anchorage fromtakes anchorage from
the chin or foreheadthe chin or forehead
or both for theor both for the
anterior traction of theanterior traction of the
maxilla using extra-maxilla using extra-
oral elastics whichoral elastics which
generate largegenerate large
amounts of forceamounts of force

COMPONENTS OF ORTHOEDIC
FACIAL MASK THERAPY
The component of facial maskThe component of facial mask
applianceappliance
 Facial MaskFacial Mask
– Chin cupChin cup
– Forehead capForehead cap
– Metal frameMetal frame
 Intra-oral applianceIntra-oral appliance
– Bonded maxillary splintBonded maxillary splint
 Heavy elasticHeavy elastic

Facial MaskFacial Mask
Chin cupChin cup::
 Most protraction head gears obtainMost protraction head gears obtain
anchorage from the chin as well as theanchorage from the chin as well as the
forehead.forehead.
 The chin cup is used to take anchorageThe chin cup is used to take anchorage
from the chin area. It is usually connectedfrom the chin area. It is usually connected
to the rest of the face mask assembly byto the rest of the face mask assembly by
means of metal rods.means of metal rods.
 The chin cup can be ready-made or can beThe chin cup can be ready-made or can be
fabricated from an impression of thefabricated from an impression of the
patient's genial region.patient's genial region.www.indiandentalacademy.comwww.indiandentalacademy.com

 Forehead capForehead cap:: The forehead supportThe forehead support
or cap or strap is used to deriveor cap or strap is used to derive
anchorage from the forehead.anchorage from the forehead.
 Metal frame:Metal frame: The main component ofThe main component of
a face mask assembly is the metala face mask assembly is the metal
frame- It connects the variousframe- It connects the various
components such as the chin cup andcomponents such as the chin cup and
forehead cap. It also has provision toforehead cap. It also has provision to
receive elastics from the intraoralreceive elastics from the intraoral
appliance. The design of the metalappliance. The design of the metal
frame differs based on the type of faceframe differs based on the type of face
mask.mask.

Intra-oral applianceIntra-oral appliance::
 The most common type of protractionThe most common type of protraction
device is a bonded appliance with rigid wire.device is a bonded appliance with rigid wire.
Traction hooks are placed either in theTraction hooks are placed either in the
deciduous molar or premolar region.deciduous molar or premolar region.
McNamara advocates a banded R.M.E. alongMcNamara advocates a banded R.M.E. along
with the protraction device which more orwith the protraction device which more or
less resembles the banded Herbst appliance.less resembles the banded Herbst appliance.
6 E D or D E C6 E D or D E Cwww.indiandentalacademy.comwww.indiandentalacademy.com

►If 2If 2ndnd
M erupted- Occlusal stop is given. NotM erupted- Occlusal stop is given. Not
included in the frame work -> bite openingincluded in the frame work -> bite opening
►High hooks-High hooks- more downward direction ofmore downward direction of
force on maxillaforce on maxilla
►Low hooks-Low hooks- more horizontal direction ofmore horizontal direction of
force on maxillaforce on maxilla
►The limiting factors- vestibule & relativeThe limiting factors- vestibule & relative
position of both the lipsposition of both the lips

 3mm thick Biocryl3mm thick Biocryl better thanbetter than coldcold
cure acryliccure acrylic
 Advantages- Better approximation toAdvantages- Better approximation to
occlusal configurationocclusal configuration
 Easy to remove as comparativelyEasy to remove as comparatively
flexibleflexible

Elastic Traction:Elastic Traction:
 The facial mask is secured to the face byThe facial mask is secured to the face by
stretching elastics from the hooks on thestretching elastics from the hooks on the
maxillary splint to the crossbow of the facialmaxillary splint to the crossbow of the facial
maskmask

Types of reverse pull head gearTypes of reverse pull head gear
 Protraction head gear by 'HickhamProtraction head gear by 'Hickham

 Face mask of DelaireFace mask of Delaire::
 Tubinger modelTubinger model

 Petit type of face maskPetit type of face mask

 New Maxillary ProtractorNew Maxillary Protractor
By Dr. ConteBy Dr. Conte

Indications:Indications:
 It can be used in a growing patientIt can be used in a growing patient
having a prognathic mandible and ahaving a prognathic mandible and a
retrusive maxilla. It aids in pulling theretrusive maxilla. It aids in pulling the
maxillary structures forward andmaxillary structures forward and
pushing the mandibular structurespushing the mandibular structures
backward.backward.
 It can be used for bending theIt can be used for bending the
condylar neck for stimulatingcondylar neck for stimulating
temporomandibular joint adaptationstemporomandibular joint adaptations
to posterior displacement of the chin.to posterior displacement of the chin.

 It can also be used for selectiveIt can also be used for selective
rearrangement of the palatal shelvesrearrangement of the palatal shelves
in cleft patients.in cleft patients.
 It can be used in correction of post-It can be used in correction of post-
surgical relapse after osteotomies (orsurgical relapse after osteotomies (or
uncontrolled post-surgicaluncontrolled post-surgical
adaptations).adaptations).
 It can be used to treat certainIt can be used to treat certain
accessory problems associated withaccessory problems associated with
nose morphology such as lateralnose morphology such as lateral
deviationsdeviations

SKELETAL EFFECTS OF MAXILLARYSKELETAL EFFECTS OF MAXILLARY
PROTRACTION ( sutures involved):PROTRACTION ( sutures involved):
 The maxilla articulates with nine other bones of theThe maxilla articulates with nine other bones of the
craniofacial complex:craniofacial complex: frontal, nasal, lacrimal,frontal, nasal, lacrimal,
ethmoid, palatine, vomer, zygoma, inferior nasalethmoid, palatine, vomer, zygoma, inferior nasal
concha, opposite maxilla, and occasionally sphenoid.concha, opposite maxilla, and occasionally sphenoid.
 Palatal expansion had been shown to produce aPalatal expansion had been shown to produce a
forward and downward movement of the maxilla byforward and downward movement of the maxilla by
affecting the intermaxillary and circummaxillaryaffecting the intermaxillary and circummaxillary
sutures. (Delinger AJO 1973;63:509-516)sutures. (Delinger AJO 1973;63:509-516)
 The disruption of these sutures may help initiatingThe disruption of these sutures may help initiating
cellular response in the sutures, allowing a morecellular response in the sutures, allowing a more
positive reaction to protraction forces.positive reaction to protraction forces.

An anteriorly directed 1.0-kg force- on
the buccal surfaces of the maxillary first
molars
a horizontal parallel direction - The
nasomaxillary complex showed a
forward displacement with upward and
forward rotation
a 30° obliquely downward direction to
the functional occlusal plane- almost
translatory repositioning of the
complex in an anterior direction.
High stress levels were observed in
the nasomaxillary complex and its
surrounding structures.
A downward protraction force
produced relatively uniform stress
distributions, indicating the importance
of the force direction in determining
the stress distributions from various
orthopedic forces.
0.020 to 0.030 kg/mm2
on average
(AM J ORTHOD DENTOFAC ORTHOP
1989;95:200-7 Tanne K et al) www.indiandentalacademy.comwww.indiandentalacademy.com

KambaraKambara found changes at the circummaxillary suturesfound changes at the circummaxillary sutures
and at the maxillary tuberosity attributable toand at the maxillary tuberosity attributable to
posteroanterior traction, including the opening ofposteroanterior traction, including the opening of
sutures, stretching of sutural connective-tissue fibers,sutures, stretching of sutural connective-tissue fibers,
new bone deposition along the stretched fibers, andnew bone deposition along the stretched fibers, and
apparent tissue homeostasis that maintained theapparent tissue homeostasis that maintained the
sutural width.sutural width.
Nanda and HickoryNanda and Hickory showed how the histologicshowed how the histologic
modifications in the zygomatico maxillary suture aftermodifications in the zygomatico maxillary suture after
maxillary protraction varied according to themaxillary protraction varied according to the
orientation of the force system applied.orientation of the force system applied.

 Forward growth of maxillaForward growth of maxilla
4.1mm early treated group4.1mm early treated group
2.1mm late treated group2.1mm late treated group
1mm in both control group1mm in both control group
 Mandibular length (Co-Gn)Mandibular length (Co-Gn)
2mm early treated group2mm early treated group
3.5mm late treated group3.5mm late treated group
4.5mm in both control group4.5mm in both control group
McNamara et alMcNamara et al AJODO 1998;113:333-343AJODO 1998;113:333-343

 More forward and upward direction ofMore forward and upward direction of
condylar growth in early treated subjectscondylar growth in early treated subjects
 ““ANTERIOR MORPHOGENETICANTERIOR MORPHOGENETIC
ROTATION”-ROTATION”- Of the mandible , is aOf the mandible , is a
biological process that is able to dissipatebiological process that is able to dissipate
excess of mandibular growth relative toexcess of mandibular growth relative to
the maxilla, and it has been reported as athe maxilla, and it has been reported as a
major effect of early functional treatmentmajor effect of early functional treatment
of Cl-III malocclusion.of Cl-III malocclusion.
AJODO 1996;109:310-318AJODO 1996;109:310-318

 Cl-III craniofacial growth pattern isCl-III craniofacial growth pattern is
re-established within 1yr of postre-established within 1yr of post
treatment observation in absence oftreatment observation in absence of
any retention appliance.any retention appliance.
McNamara et al AJODO 2000;118:404-413McNamara et al AJODO 2000;118:404-413

BIOMECHANICS:BIOMECHANICS:
The centre of resistance of the maxilla isThe centre of resistance of the maxilla is
located at the distal contacts of the maxillarylocated at the distal contacts of the maxillary
first molars, one half the distance from thefirst molars, one half the distance from the
functional occlusal plane to the inferiorfunctional occlusal plane to the inferior
border of the orbit.(border of the orbit.( Lee AJO 1997Lee AJO 1997))
Protraction of maxilla below the Centre ofProtraction of maxilla below the Centre of
resistance produces counter clock wiseresistance produces counter clock wise
rotation of the maxilla. Alsorotation of the maxilla. Also Hata et al (AJOHata et al (AJO
1987)1987) found using human skulls thatfound using human skulls that
protraction forces at the level of theprotraction forces at the level of the
maxillary arch produces forward but countermaxillary arch produces forward but counter
clock wise rotation unless a heavy downwardclock wise rotation unless a heavy downward
vector of force was applied.vector of force was applied.

BioBio
mechanicsmechanics

 AA heavy force at 300 -450 gmsheavy force at 300 -450 gms onon
either side at abouteither side at about 303000
to the functionalto the functional
occlusal plane in both primary and mixedocclusal plane in both primary and mixed
dentition is recommended by mostdentition is recommended by most
authors producingauthors producing 10 degree of counter10 degree of counter
clock wise rotationclock wise rotation being acceptable .being acceptable .
 Direction of force:Direction of force: Downwards andDownwards and
forwardsforwards
 Point of Application:Point of Application: 5 mm above the5 mm above the
palatal plane in the canine region.palatal plane in the canine region.
 Hata et alHata et al suggested that an effectivesuggested that an effective
forward displacement of the maxilla canforward displacement of the maxilla can
be obtained with this point of applicationbe obtained with this point of application

Timing of Face Mask TherapyTiming of Face Mask Therapy
 Evidence shows early mixedEvidence shows early mixed
dentition is better than the latedentition is better than the late
mixed dentition at the time of initialmixed dentition at the time of initial
eruption of maxillary central incisorseruption of maxillary central incisors
McNamara et alMcNamara et al AJODO 1998;113:333-343AJODO 1998;113:333-343

Bjork Trans Eur Orthod Soc 1964;40:48-64
Sutural growth in boys normally ceases by 17yrs
AJO 1977;72:42-52
Intermaxillary suture is closed at 18yrs, although
patency has been reported in some subjects at
28yrs.

CLINICAL MANEGEMENT OF FACE MASKCLINICAL MANEGEMENT OF FACE MASK
 Splint activation-Splint activation- once per day beforeonce per day before
bed time until the desired increase inbed time until the desired increase in
transverse width has been achievedtransverse width has been achieved..
 Patient in whom no increase inPatient in whom no increase in
transverse dimension is desired, thetransverse dimension is desired, the
appliance stillappliance still activated for 8-10 daysactivated for 8-10 days
to disrupt the maxillary sutural systemto disrupt the maxillary sutural system
and to promote maxillary protractionand to promote maxillary protraction
(HASS 1965)(HASS 1965)

SEQUENCE OF ELASTICS:SEQUENCE OF ELASTICS:
 At the time of delivery 3/8” 8 oz 2 weeksAt the time of delivery 3/8” 8 oz 2 weeks
 After 2 weeks added 1/2” B/LAfter 2 weeks added 1/2” B/L
 Increased to a max. of 5/16” 14 ozIncreased to a max. of 5/16” 14 oz
 Timing of wear:Timing of wear:
– Young patients (4 - 9 years) should wearYoung patients (4 - 9 years) should wear
the mask on a full time basis except duringthe mask on a full time basis except during
meals.meals.
– In older patients, it is worn at all timesIn older patients, it is worn at all times
except during schoolexcept during school
 DurationDuration is 4-6 months. Follow up everyis 4-6 months. Follow up every
4-8wks4-8wks

Discontinuation of treatmentDiscontinuation of treatment
►After 2-5mm positive OJ achievedAfter 2-5mm positive OJ achieved
►3-6month night time wear only3-6month night time wear only
►Retained:Retained: with a maintenance plate, chinwith a maintenance plate, chin
cup, FR III, removable mandibular retractorcup, FR III, removable mandibular retractor
or a modified utility arch with Class IIIor a modified utility arch with Class III
elastics.elastics.
►Discontinued if any symptoms of TMD isDiscontinued if any symptoms of TMD is
seenseen

Treatment Effects Produced byTreatment Effects Produced by
Facial Mask Therapy:Facial Mask Therapy:
FIGER SHOWES Forward traction against the
maxilla typically has three effects: (1) some
forward movement of the maxilla, the amount
depending to a large extent on the patients age;
(2) forward movement of the maxillary teeth
relative to the maxilla; and (3) downward and
backward rotation of the mandible because of the
reciprocal force placed against the chin.

MOLAR CORRECTION
3.8mm
(100%)
Skeletal Changes
3.2mm
(84%)
Dental Changes
0.6mm
(16%)
Maxilla
1.9mm Forward
(49%)
Mandible
1.3mm Backward
(35%)
Differential movement of maxillary
molars (2.0mm forward) and
mandibular molars (1.4mm forward)
Fig.21-18 Skeletal and dental contributions to molar correction with maxillary
expansion and protraction.

OVERJET CORRECTION
6.1mm
(100%)
Skeletal Changes
3.1mm
(52%)
Dental Changes
2.9mm
(48%)
Maxilla
1.9mm Forward
(31%)
Mandible
1.3mm Backward
(21%)
Maxilla Incisors
1.7mm Forward
(28%)
Mandible Incisors
1.2mm Backward
(20%)
Fig.21-17 Skeletal and dental contributions to overjet correction with maxillary expansion
and protraction.

Sites of anchorageSites of anchorage
Anchorage for the purpose of maxillaryAnchorage for the purpose of maxillary
retraction is currently obtained fromretraction is currently obtained from
 1. Anchorage from skull (forehead)1. Anchorage from skull (forehead)
 2. Anchorage from chin2. Anchorage from chin
 3. Anchorage from chin & forehead3. Anchorage from chin & forehead

Long-term effects of Class III treatment with rapid maxillary expansion and
facemask therapy followed by fixed appliances
J A. McNamara, Jr, Baccetti, Lorenzo Franchi, D. M. Sarver,
(Am J Orthod Dentofacial Orthop 2003;123:306-20)
1. Treatment with RME/FM therapy for 10 months (T1to T2) induced a
significant response of the craniofacial skeleton in terms of forward
movement of the maxilla and downward and backward movement of the
mandible.
2. Although Class III craniofacial characteristics were re-established in the
posttreatment period, postprotraction (T2 to T3) growth did not display
significant relapse in any cephalometric measure.
3. Overall, RME/FM therapy was shown to be an effective treatment for
correcting skeletal Class III malocclusion in the long term (T1 to T3). The
favorable skeletal effects induced before the pubertal growth spurt with
orthopedic facemask therapy led to the establishment of a positive overbite
and overjet relationship. The occlusal relationships generally withstood
subsequent Class III craniofacial growth throughout attainment of skeletal
maturity as assessed by the CVM method.

 Does RME enhance the efficiency ofDoes RME enhance the efficiency of
maxillary protraction with face maskmaxillary protraction with face mask
in developing Class IIIin developing Class III
malocclusion?malocclusion?
 Results: Face mask therapy effectiveResults: Face mask therapy effective
in early Class III MOin early Class III MO
 The need for palatal expansion inThe need for palatal expansion in
the absence of a transversethe absence of a transverse
discrepancy or a skeletal/ dentaldiscrepancy or a skeletal/ dental
cross bite is not supported.cross bite is not supported.
 Correction due to combined skeletalCorrection due to combined skeletal
and dental changeand dental change..
AJO DO 2005 128; 299-309AJO DO 2005 128; 299-309

Critical appraisalCritical appraisal
 The skeletal change followingThe skeletal change following
protraction is significant.protraction is significant.
 But has no correlation withBut has no correlation with
expansion.expansion.
Kalha A S: EBD 2006:7(1),16-17Kalha A S: EBD 2006:7(1),16-17www.indiandentalacademy.comwww.indiandentalacademy.com

CAUTION ! !CAUTION ! !
►Older the patient & more severe theOlder the patient & more severe the
malocclusion --malocclusion -- surgerysurgery
►Strong family history of mandibularStrong family history of mandibular
prognathismprognathism
►Early dentoalveolar features likeEarly dentoalveolar features like
Excessive intermaxillary vertical relationship (skeletalExcessive intermaxillary vertical relationship (skeletal
open bite)open bite)
Posterior inclination of mandibular condylePosterior inclination of mandibular condyle
Large mandibular intermolar widthLarge mandibular intermolar width
AJODO 1997;112:80-86AJODO 1997;112:80-86www.indiandentalacademy.comwww.indiandentalacademy.com

 In approaximately 50% of mixedIn approaximately 50% of mixed
dentition face mask therapy a 2dentition face mask therapy a 2ndnd
intervention is needed before theintervention is needed before the
fixed appliancwe therapyfixed appliancwe therapy
RME or Reintroduction of facialRME or Reintroduction of facial
maskmask

CHIN CUPCHIN CUP
 The chin cup or the chin cap as it isThe chin cup or the chin cap as it is
sometimes referred to is an extra-oralsometimes referred to is an extra-oral
orthopedic device that covers the chin and isorthopedic device that covers the chin and is
connected to a head gear. It is used toconnected to a head gear. It is used to
restrict the forward and downward growth ofrestrict the forward and downward growth of
the mandiblethe mandible

Components of Chin Cup:Components of Chin Cup:
 The chin cup-face bow assemblyThe chin cup-face bow assembly
consists of a chin cup that covers theconsists of a chin cup that covers the
chin, a head cap and an adjustablechin, a head cap and an adjustable
elastic strap that connects the chinelastic strap that connects the chin
cup with the head cap.cup with the head cap.

Types of Chin CupTypes of Chin Cup
 Chin cups can be divided into twoChin cups can be divided into two
types, based on the direction of pull:types, based on the direction of pull:
occipital-pull and vertical-pull.occipital-pull and vertical-pull.

Occipital Chin Cup :Occipital Chin Cup :
 The occipital-pull chin cup is theThe occipital-pull chin cup is the
more frequently used type of chincupmore frequently used type of chincup
treatment for Class III malocclusion.treatment for Class III malocclusion.
This chin cup is indicated in instancesThis chin cup is indicated in instances
of mild to moderate mandibularof mild to moderate mandibular
prognathism and is best initiatedprognathism and is best initiated
during the late deciduous or earlyduring the late deciduous or early
mixed dentition.mixed dentition.

IndicationIndication
 Mild to moderate mandibularMild to moderate mandibular
prognathismprognathism
 Edge to edge incisors in centricEdge to edge incisors in centric
relation & increase in lower facial htrelation & increase in lower facial ht
is not requiredis not required
 Mandibular prognathism & shortMandibular prognathism & short
lower facelower face
 Normal or slightly proclinedNormal or slightly proclined
mandibular incisorsmandibular incisors

Force Magnitude and Direction :Force Magnitude and Direction :
 At the time of appliance delivery aAt the time of appliance delivery a
force of 150-300 grams per side isforce of 150-300 grams per side is
used. Over the next two months theused. Over the next two months the
force is gradually increased to 450-force is gradually increased to 450-
700 grams per side(16-24 oz)700 grams per side(16-24 oz)
 14hrs/day (10-16hrs acceptable14hrs/day (10-16hrs acceptable
range) including sleeprange) including sleep

 Use of occipital chin cup as early asUse of occipital chin cup as early as
practically possiblepractically possible
Effective timing for the application of orthopedic force in the skeletal Class IIIEffective timing for the application of orthopedic force in the skeletal Class III
malocclusion Toshihiko Sakamoto AJO1981;80:411-416malocclusion Toshihiko Sakamoto AJO1981;80:411-416
 There is little evidence to date, thatThere is little evidence to date, that
supports the concept that thesupports the concept that the
ultimate length of the mandible isultimate length of the mandible is
influenced significantly by chin cupinfluenced significantly by chin cup
therapy.therapy.
McNamara & BrudonMcNamara & Brudon

Vertical Pull Chin Cup :Vertical Pull Chin Cup :
 Vertical-pull chin cups are applicable notVertical-pull chin cups are applicable not
only in Class III patients with anterioronly in Class III patients with anterior
open bite tendencies but also can be usedopen bite tendencies but also can be used
in patients who have an increased anteriorin patients who have an increased anterior
vertical dimension.vertical dimension.
 PearsonPearson hashas rereported that the use of aported that the use of a
vertical-pull chin cup can result in avertical-pull chin cup can result in a
decrease in the mandibular plane anddecrease in the mandibular plane and
gonial angles and an increase in posteriorgonial angles and an increase in posterior
facial height, in comparison to the growthfacial height, in comparison to the growth
of untreated individuals.of untreated individuals.
AO 1986;56:205-224AO 1986;56:205-224www.indiandentalacademy.comwww.indiandentalacademy.com

 Pearson recommends use ofPearson recommends use of
posterior bite blocks in conjunctionposterior bite blocks in conjunction
with vertical –pull chin cupwith vertical –pull chin cup

 Pearson recommend 500g /side –Pearson recommend 500g /side –
12hrs/day.12hrs/day.
 Vertical –pull chin cup – force vectorVertical –pull chin cup – force vector
909000
to the Occlusal plane, passingto the Occlusal plane, passing
through the Cres of the arch.through the Cres of the arch.
Force Magnitude and Direction :

Treatment effectTreatment effect
The orthopedic effects of a chin cupThe orthopedic effects of a chin cup
on the mandible includeon the mandible include
 redirection of mandibular growthredirection of mandibular growth
vertically,vertically,
 backward repositioning (rotation) ofbackward repositioning (rotation) of
the mandible, andthe mandible, and
 remodeling of the mandible withremodeling of the mandible with
closure of gonial angle.closure of gonial angle.

There are two main
approaches to chin
cup therapy, as
shown
diagrammatically
here; the force aimed
directly at the
condylar area, or
lighter force if aimed
below the condyle to
produce downward
rotation of the
mandible

Diagrammatic representation of a
typical response to chin cup therapy,
showing the downward & backward
rotation of the mandible accompanied
by an increase in facial height.

Treatment Timing & DurationTreatment Timing & Duration
 Patient with mandibular excess can usuallyPatient with mandibular excess can usually
be recognized in the primary dentitionbe recognized in the primary dentition
despite the fact that the mandible appearsdespite the fact that the mandible appears
retrognathic in the early years for mostretrognathic in the early years for most
children.children.
 Evidence exists that treatment to reduceEvidence exists that treatment to reduce
mandibular protrusion is more successfulmandibular protrusion is more successful
when it is started in thewhen it is started in the primary or earlyprimary or early
mixed dentition.mixed dentition.
 The treatment time varies from 1 year toThe treatment time varies from 1 year to
as long as 4 years depending on theas long as 4 years depending on the
severity of the original malocclusion.severity of the original malocclusion.

Ideal Patient for chin cup:Ideal Patient for chin cup:
 A mild skeletal problem with theA mild skeletal problem with the
ability to bring the incisor edge toability to bring the incisor edge to
edge, short vertical facial height,edge, short vertical facial height,
normally positional or protrusive, butnormally positional or protrusive, but
not retrusive lower incisors.not retrusive lower incisors.

CAUTION ! !CAUTION ! !
 In general chin-cup does not show toIn general chin-cup does not show to
produce any TMJ symptoms inproduce any TMJ symptoms in
growing patientsgrowing patients (Graber 1997)(Graber 1997)
 If it arises therapy should beIf it arises therapy should be
terminatedterminated

Chin Cup Treatment Outcomes in Skeletal Class III
Dolicho Versus Nondolichofacial Patients
Yoshiro Iida, Toshio Deguchi Sr,Toru Kageyama
x The treatment period and wear time of the chin cup appliance in
nondolichofacial (mostly mesiofacial pattern) patients can be shorter
than those of dolichofacial patients.
x All subjects showed significant improvement of dolicho-
or nondolichofacial skeletal Class III malocclusion.
x The treatment outcome in the two groups maintained the original
characteristics of skeletal morphology at retention.
x Not only horizontal but also vertical improvements of skeletal Class
III abnormalities were obtained with excellent patient compliance.
Angle Orthod 2005;75:502–509

Profile Changes Associated with Different Orthopedic
Treatment Approaches in Class III Malocclusions
Ayc¸a Arman et al
(Angle Orthod 2004;74:731–738.)
x Significant dentoskeletal changes and improvements in
dentofacial profile were achieved with all the orthopedic
treatment modalities.
X Soft tissue profile improvements in the maxillary region
were more prominent and similar in CCBP and RHg
groups.
X In the mandibular region, the soft tissue changes were
pronounced in CC and CCBP groups.
X Long-term studies are required to confirm the stability of
these changes.
CCBP-chin cup bite plate,CC- chin cup,RHg- reverse headgear

Small doses of oscillatory mechanical force have the potential to
modulate Sutural growth effectively either accelerating it or
initiating net Sutural bone resorption for various therapeutic
objectives (as few as 5N, 600cycles/sec for 10min/day over
12dys).
J Dnt Res 2002; 81(12):810-816
Orthod Craniofacial Res 2006;9:111-122 S.M. Alaqeel et al
The molecular response of sutures to force magnitude needs
to be futher investigated as these molecules can be used to
enhance the way in which craniofacial sutures respond to
mechanical force during orthopaedic- orthdontic treatment.
Rabie et al
Increase in Vascular Endothelial Growth Factor/ VEGF
Increase in SOX-9 gene
Increase in new bone formation
AJODO 2003;123:40-48
AJODO 2004;126(4):353-358
AJODO 2002;122:401-409

The amount & direction of TMJ changes were only temporarily affected
favourably.
Pancherz, Fischer AO 2003;73:493-50
McNamara Jr et al AJODO 2006;129(5):599.e1-599e12
AJODO 2002;122:470-476

CONCLUSIONCONCLUSION
 Extraoral orthopedic appliance hasExtraoral orthopedic appliance has
proved to be a dependable methodproved to be a dependable method
of class II and class III correction forof class II and class III correction for
over 100 years and this treatmentover 100 years and this treatment
adjunct is used with varyingadjunct is used with varying
frequency world wide.frequency world wide.
 The major “Achilles heal” in thisThe major “Achilles heal” in this
method is as with other methodsmethod is as with other methods
that involve participation of thethat involve participation of the
patient in the treatment process, i:e:patient in the treatment process, i:e:
patient co-operation.patient co-operation.www.indiandentalacademy.comwww.indiandentalacademy.com

 When the extra oral orthopedicWhen the extra oral orthopedic
appliance is prescribed for patient whoappliance is prescribed for patient who
is compliant, effective and efficientis compliant, effective and efficient
treatment is the result.treatment is the result.

REFERENCESREFERENCES
 ARMSTRONG. M.M.: Controlling the magnitude directionARMSTRONG. M.M.: Controlling the magnitude direction
and duration of extra oral force. Am. J. Orthod. 59; 277.and duration of extra oral force. Am. J. Orthod. 59; 277.
1971.1971.
 BANKS, and READ: An investigation into the reliabilitiesBANKS, and READ: An investigation into the reliabilities
of the timing headgear. Brit .J. Orthod. 14; 263, 1987.of the timing headgear. Brit .J. Orthod. 14; 263, 1987.
 BAUMRIND. S and KORN, E.L.: Patterns of change inBAUMRIND. S and KORN, E.L.: Patterns of change in
mandibular and facial shape associated with the use ofmandibular and facial shape associated with the use of
forces to retract the maxilla Am. J. ORTHOD. 08; 17, 32,forces to retract the maxilla Am. J. ORTHOD. 08; 17, 32,
1981.1981.
 BEGG. P.R. and KESLING P.C.: Begg OrthodonticBEGG. P.R. and KESLING P.C.: Begg Orthodontic
Technique and Theory. W.B. Saunders Co. 1971.Technique and Theory. W.B. Saunders Co. 1971.
 CLARK. W.J.: The twin block technique. Am. J. Orthod.CLARK. W.J.: The twin block technique. Am. J. Orthod.
93; 1, 1988.93; 1, 1988.
 CHACONAS. S.J.: Orthodontics Post-graduate dentalCHACONAS. S.J.: Orthodontics Post-graduate dental
handbook. Vol-10. John Wright 1982.handbook. Vol-10. John Wright 1982.
 CHACONAS. S.J.: CAPUTO A.A. et al: The effect ofCHACONAS. S.J.: CAPUTO A.A. et al: The effect of
orthopedic forces on the cranio facial complex utilizingorthopedic forces on the cranio facial complex utilizing
(forces) cervical and headgear appliances. Am. J. Orthod.(forces) cervical and headgear appliances. Am. J. Orthod.
69; 527, 1976.69; 527, 1976. www.indiandentalacademy.comwww.indiandentalacademy.com

 CHACONAS. S.J.: Orthopedic effect of the extra-oral chin-CHACONAS. S.J.: Orthopedic effect of the extra-oral chin-
cup appliance on the mandible. Am. J. Orthod. 69; 29,cup appliance on the mandible. Am. J. Orthod. 69; 29,
1976.1976.
 DOUGHERTLY and BEAZLY: A bio-differential system of face-DOUGHERTLY and BEAZLY: A bio-differential system of face-
bow mechanics. Am. J. Orthod. 70; 505, 1976.bow mechanics. Am. J. Orthod. 70; 505, 1976.
 FREEMAN, ROBERT: Mandibular cervical gear to gain or toFREEMAN, ROBERT: Mandibular cervical gear to gain or to
regain arch length. Am. J. Orthod. 94: 21. 1988.regain arch length. Am. J. Orthod. 94: 21. 1988.
 GOULD. I.E.: Mechanical principles of extra-oral anchorage.GOULD. I.E.: Mechanical principles of extra-oral anchorage.
Am. J. Orthod. 43; 319, 1957.Am. J. Orthod. 43; 319, 1957.
 HOWARD. R.D.: Skeletal changes with extra oral traction.HOWARD. R.D.: Skeletal changes with extra oral traction.
Eut. J. Orthod. 4, 197, 1982.Eut. J. Orthod. 4, 197, 1982.
 JACOESON, ALEX: A key to understanding extra oral forces.JACOESON, ALEX: A key to understanding extra oral forces.
Am. J. Orthod. 75; 361, 1979.Am. J. Orthod. 75; 361, 1979.
 KLOEHIN. S.J.: Evaluation of cervical anchorage force inKLOEHIN. S.J.: Evaluation of cervical anchorage force in
treatment. Angle Orthod. 31; 91, 1961.treatment. Angle Orthod. 31; 91, 1961.
 LEVIN. R.I.: Activator headgear therapy. Am. J. Orthod. 87;LEVIN. R.I.: Activator headgear therapy. Am. J. Orthod. 87;
91, 1985.91, 1985.
 LINDQUIST. J.T.: The edgewise appliance in orthodontics –LINDQUIST. J.T.: The edgewise appliance in orthodontics –
current principles and practice. Graber and Swain; C.V.current principles and practice. Graber and Swain; C.V.
Mosby Co – 1985.Mosby Co – 1985.

 Mc NAMARA. L.A. Jr: Neuromuscular and skeletal adaptations toMc NAMARA. L.A. Jr: Neuromuscular and skeletal adaptations to
altered orofacial function. Monograph – 1, Craniofacial growthaltered orofacial function. Monograph – 1, Craniofacial growth
series. Ann Arbor, Michigan. 1972.series. Ann Arbor, Michigan. 1972.
 MERRIFIELD. L.L. and CROSS. J.J.: Directional forces. Am. J.MERRIFIELD. L.L. and CROSS. J.J.: Directional forces. Am. J.
Orthod. 57;4355, 1971.Orthod. 57;4355, 1971.
 MAGNI, FRANCO; The activated face-bow simple safety extra-oralMAGNI, FRANCO; The activated face-bow simple safety extra-oral
traction. Am. J. Orthod. 75; 152, 1979.traction. Am. J. Orthod. 75; 152, 1979.
 NIKOLAI. R.J.: An optimum orthodontic force theory as applied forNIKOLAI. R.J.: An optimum orthodontic force theory as applied for
canine retraction. Am. J. Orthod. 68; 290, 1975.canine retraction. Am. J. Orthod. 68; 290, 1975.
 PETROVIC. A; STUTZMAN. J. and OUDET. C.L.: Control processesPETROVIC. A; STUTZMAN. J. and OUDET. C.L.: Control processes
in the postnatal growth of condylar cartilage. In Mc Namara J.A.in the postnatal growth of condylar cartilage. In Mc Namara J.A.
Monograph – 4. Craniofacial growth series. Ann Arbon, Michigan,Monograph – 4. Craniofacial growth series. Ann Arbon, Michigan,
1975.1975.
 PETROVIC. A. STUXMAN. J. and GASSON. N: Is periodic forwardPETROVIC. A. STUXMAN. J. and GASSON. N: Is periodic forward
repositioning the best procedure to elicit over lengthening? Inrepositioning the best procedure to elicit over lengthening? In
Carlson. D.S. and Ribben, editors: Craniofacial biology, MonographCarlson. D.S. and Ribben, editors: Craniofacial biology, Monograph
– 10, Craniofacial growth series. Ann Arbon. Michigan. 1981.– 10, Craniofacial growth series. Ann Arbon. Michigan. 1981.
 PFEIFER. J.P. and CROBETY. D.: The Class II malocclusion:PFEIFER. J.P. and CROBETY. D.: The Class II malocclusion:
differential diagnosis and clinical application of activators, extradifferential diagnosis and clinical application of activators, extra
oral forces and fixed appliances. Am. J. Orthod. 68; 499, 1975.oral forces and fixed appliances. Am. J. Orthod. 68; 499, 1975.
 POULTION. D.R.: The influence of extra oral traction. Am. J.POULTION. D.R.: The influence of extra oral traction. Am. J.
Orthod. 53;8, 1967.Orthod. 53;8, 1967.
 PROFFIT. W.R.: P.P. 211 Contemporary orthodontics, C.V. MosbyPROFFIT. W.R.: P.P. 211 Contemporary orthodontics, C.V. Mosby
Co. 1986.Co. 1986.

 RICKETTS. R.M.: The influence of orthodontic treatment inRICKETTS. R.M.: The influence of orthodontic treatment in
facial growth and development. Angle Orthod. 30; 103,facial growth and development. Angle Orthod. 30; 103,
1960.1960.
 RICKETTS. R.M.: Mechanisms of mandibular growth. In McRICKETTS. R.M.: Mechanisms of mandibular growth. In Mc
Namara. J.A. editor: Monograph – 4, Craniofacial growthNamara. J.A. editor: Monograph – 4, Craniofacial growth
series. Ann Arbor. Michigan – 1975.series. Ann Arbor. Michigan – 1975.
 RICKETTS. R.M.: BENCH, R.W.: and GUGIND. C.T.: Bio-RICKETTS. R.M.: BENCH, R.W.: and GUGIND. C.T.: Bio-
progressive therapy, Denver. Rocky Mountain Orthod. 1979.progressive therapy, Denver. Rocky Mountain Orthod. 1979.
 ROOT. T.I.: JOC Interviews: Dr. Terrel. L. Root onROOT. T.I.: JOC Interviews: Dr. Terrel. L. Root on
Headgear. J. Clin. Orthod. 90. 20. 1975.Headgear. J. Clin. Orthod. 90. 20. 1975.
 ROOT. R.H.: Treatment mechanics for the straight wireROOT. R.H.: Treatment mechanics for the straight wire
appliance. Orthodontics – current principles and practice.appliance. Orthodontics – current principles and practice.
Graber and Swain. C.V. Mosby. Co. 1985.Graber and Swain. C.V. Mosby. Co. 1985.
 SABDYSKY. Cephalometric evaluation of the Kloehn type ofSABDYSKY. Cephalometric evaluation of the Kloehn type of
cervical traction. Am. J. Orthod. 51; 262, 1965.cervical traction. Am. J. Orthod. 51; 262, 1965.
 STOCKLI. P.W. A growth related concept for skeletal Class IISTOCKLI. P.W. A growth related concept for skeletal Class II
treatment. Am. J. Orthod. 74; 258, 1978.treatment. Am. J. Orthod. 74; 258, 1978.
 TEUSHER. U.M.: A growth related concept for skeletal ClassTEUSHER. U.M.: A growth related concept for skeletal Class
II treatment. Am. J. Orthod. 74; 258, 1978.II treatment. Am. J. Orthod. 74; 258, 1978.
 THUROW. R.C. Craniomaxillary orthopedic correction withTHUROW. R.C. Craniomaxillary orthopedic correction with
enmasse dental control. Am. J. Orthod. 68; 601, 1975.enmasse dental control. Am. J. Orthod. 68; 601, 1975.
 THUROW. P.: Atlas of orthodontic principles. C.V. Mosby,THUROW. P.: Atlas of orthodontic principles. C.V. Mosby,
Co. 1970.Co. 1970.

 WIESLANDER. L.: The effect of force of craniofacialWIESLANDER. L.: The effect of force of craniofacial
development. Am. J. Orthod. 65;531, 1974.development. Am. J. Orthod. 65;531, 1974.
 WIESLANDER. L.: J.C.O/Interviews on dentofacialWIESLANDER. L.: J.C.O/Interviews on dentofacial
orthopedics Headgear Herbst treatment in the mixedorthopedics Headgear Herbst treatment in the mixed
dentition. J. Clin. Orthod. 18; 551, 1984.dentition. J. Clin. Orthod. 18; 551, 1984.
 WIESLANDER. L.: Intensive treatment of severe Class IIWIESLANDER. L.: Intensive treatment of severe Class II
malocclusion with a headgear – Herbst appliance. Am. J.malocclusion with a headgear – Herbst appliance. Am. J.
Orthod. 86;1, 1984.Orthod. 86;1, 1984.
 WORMS. F.W. et al: A concept and classification of rotationWORMS. F.W. et al: A concept and classification of rotation
and extra oral force systems. Angle Orthod. 43; 384, 1973.and extra oral force systems. Angle Orthod. 43; 384, 1973.
 GRABER. T.M.: Orthodontics principles and practice.GRABER. T.M.: Orthodontics principles and practice.
Philadelphia: W.B. Saunders Co.; 2001.Philadelphia: W.B. Saunders Co.; 2001.
 PROFFIT. W.R.: Contemporary orthodontics. St. Louis: C.V.PROFFIT. W.R.: Contemporary orthodontics. St. Louis: C.V.
Mosby Company; 2000.Mosby Company; 2000.
 FRANKEL. R, FRANKEL. C.: Orofacial orthopedics with theFRANKEL. R, FRANKEL. C.: Orofacial orthopedics with the
functional regulator. Basel : Karger; 1989.functional regulator. Basel : Karger; 1989.
 CLARK. W.J.: Twin Block functional therapy. London: MosbyCLARK. W.J.: Twin Block functional therapy. London: Mosby
– Wolte; 1995.– Wolte; 1995.
 GRABER. T.M., VANARSDALL R.L.: Orthodontics currentGRABER. T.M., VANARSDALL R.L.: Orthodontics current
principles and techniques. St. Louis: Mosby; 2000.principles and techniques. St. Louis: Mosby; 2000.

Dfo

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Dfo

Similar to Dfo (20)

More from Indian dental academy

More from Indian dental academy (20)

Recently uploaded

Recently uploaded (20)

Dfo

Editor's Notes