Dentofacialorthopedics

DENTOFACIALORTHOPEDIDENTOFACIALORTHOPEDI
CSCS
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
 Maxillary splint - Headgear CombinationMaxillary splint - Headgear Combination
 Activator - Headgear CombinationActivator - Headgear Combination
 Frankel - Headgear CombinationFrankel - Headgear Combination
www.indiandentalacademy.com

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

INTRODUCTIONINTRODUCTION
►The term orthopedics derives from GreekThe term orthopedics derives from Greek
and literally means “proper education”and literally means “proper education”
consequently the fundamental principle ofconsequently the fundamental principle of
orofacial orthopedics is to aim at optimizingorofacial orthopedics is to aim at optimizing
the development of the structures i.e., tothe development of the structures i.e., to
remove restrictions or retardation’s in theremove restrictions or retardation’s in the
accomplishment of growth patternaccomplishment of growth pattern

►The border description of “dentofacialThe border description of “dentofacial
orthopedics” conveys the concept thatorthopedics” conveys the concept that
treatment aims to improve not only dentaltreatment aims to improve not only dental
and orthopedic relationships in theand orthopedic relationships in the
stomatognathic system but also facialstomatognathic system but also facial
balance.balance.
►The adoption of a wider definition has theThe adoption of a wider definition has the
advantage of extending the zones of theadvantage of extending the zones of the
profession as well as educating public toprofession as well as educating public to
appreciate the benefits of dentofacialappreciate the benefits of dentofacial
therapy in more comprehensive aesthetictherapy in more comprehensive aesthetic
termsterms

►Ideally dentofacial orthopedic includes thoseIdeally dentofacial orthopedic includes those
appliance that are classified underappliance that are classified under
functional jaw orthopedics, it would be morefunctional jaw orthopedics, it would be more
appropriate to discuss those appliance thatappropriate to discuss those appliance that
have their effects or action primarilyhave their effects or action primarily
targeted towards the skeletal tissue rathertargeted towards the skeletal tissue rather
than the soft tissue therefore the seminar isthan the soft tissue therefore the seminar is
limited to extraoral orthopedic appliance likelimited to extraoral orthopedic appliance like
head gear, facial mask & chin cup.head gear, facial mask & chin cup.

History Of Extraoral OrthopedicHistory Of Extraoral Orthopedic
ApplianceAppliance
►An extraoral appliances in the form of a skullAn extraoral appliances in the form of a skull
cap in combination with a chin cup, wascap in combination with a chin cup, was
used in the early nineteenth centuryused in the early nineteenth century
►. The chin cup was used by Celler in 1802. The chin cup was used by Celler in 1802
and a year latter by Fox as a occipitaland a year latter by Fox as a occipital
anchorage in cases of luxation and not foranchorage in cases of luxation and not for
occipital anchorage as of today.occipital anchorage as of today.

Chin-cap devised by Fax, 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 anchorage inheadgear for occipital anchorage in
1822 or 1823.1822 or 1823.
►Kneissel {1863} published a report onKneissel {1863} published a report on
the headgear or occipital anchorage forthe headgear or occipital anchorage for
the correction of mandibular protrusion.the correction of mandibular protrusion.

►Guilford {1866} used the headgearGuilford {1866} used the headgear
for reducing protruding mandiblesfor reducing protruding mandibles
as for correcting protrudingas for correcting protruding
maxillary incisor teeth .maxillary incisor teeth .
►Schange {1884}wrote on the use ofSchange {1884}wrote on the use of
headgear.headgear.

►In 1892 Kingsley described a technique forIn 1892 Kingsley described a technique for
driving maxillary teeth distally by means of adriving maxillary teeth distally by means of a
headgear without extracting teeth . Thisheadgear without extracting teeth . This
headgear consisted of a cloth covering theheadgear consisted of a cloth covering the
back and top of head the pulling force wasback and top of head the pulling force was
transmitted by elastic.transmitted by elastic.

►Angle advocated the head cap forAngle advocated the head cap for
shortening the arch by reducing theshortening the arch by reducing the
canines.canines.

►Case in the early 1900s used extraCase in the early 1900s used extra
oral anchorage extensively in theoral anchorage extensively in the
treatment of blocked-out canines.treatment of blocked-out canines.
►Oppenheim reintroduced theOppenheim reintroduced the
extraoral appliances in 1936.extraoral appliances in 1936.

►Further modifications to this were madeFurther modifications to this were made
by Farrar, Goddard, Angle, Maccoy,by Farrar, Goddard, Angle, Maccoy,
Jackson, Kloehn and othersJackson, Kloehn and others
Headgear as used by
Farrar (1836)

ORTHODONTICS ANDORTHODONTICS AND
ORTHOPEDICS FORCESORTHOPEDICS FORCES
► In orthodontic basically two types of forces one isIn orthodontic basically two types of forces one is
an orthodontic forces that moves teeth efficientlyan orthodontic forces that moves teeth efficiently
and other an orthopedic force that affects theand other an orthopedic force that affects the
deeper craniofacial structures, orthodontic forcesdeeper craniofacial structures, orthodontic forces
are those that are applied to the teeth by means ofare those that are applied to the teeth by means of
wires and active components of the removable orwires and active components of the removable or
fixed appliance. The force produced by thesefixed appliance. The force produced by these
appliances are light and range from 50 – 100gms.appliances are light and range from 50 – 100gms.
The orthopedic force on the other hand are heavyThe orthopedic force on the other hand are heavy
forces of over 400gms.forces of over 400gms.

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

►Graber advocates a force application ofGraber advocates a force application of
more than 400gm force for 10-12 hours /more than 400gm force for 10-12 hours /
day body to restore, for healing purpose.day body to restore, for healing 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 exfoliation -150 toMixed dentition during exfoliation -150 to
250.250.
►Full permanent dentition-400 to 500.Full permanent dentition-400 to 500.
►Retention in full permanent dentition -150 toRetention in full permanent dentition -150 to
400400

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

ForceForce
►A force is that which changes or tends toA force is that which changes or tends to
change the position of rest of a body or itschange the position of rest of a body or its
uniform motion in a straight line.uniform motion in a straight line.

Center of resistanceCenter of resistance
►Every object or free body has one point onEvery object or free body has one point on
which it can be perfectly balanced. Thiswhich it can be perfectly balanced. This
point is know as thepoint is know as the center of gravitycenter of gravity
►By definition , a force with a line of actionBy definition , a force with a line of action
passing throughpassing through center of resistancecenter of resistance
producesproduces translationtranslation

Center of rotationCenter of rotation
►The center of rotation of a body is a pointThe center of rotation of a body is a point
around which the body will rotate or tip.around which the body will rotate or tip.
OROR
► Center of rotation is a point , about which aCenter of rotation is a point , about which a
body appears to have rotated , asbody appears to have rotated , as
determined form its initial and final positionsdetermined form its initial and final positions

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

Line of actionLine of action
►The line of action of a force is usuallyThe line of action of a force is usually
represented by an arrow and is the directionrepresented by an arrow and is the direction
in which the force acts.in which the force acts.

Clinical Application of AboveClinical Application of Above
PrinciplesPrinciples
► Teeth can be moved inTeeth can be moved in
only three planes ofonly three planes of
space: sagittal, coronalspace: sagittal, coronal
and transverseand transverse

Sagittal planeSagittal plane
► The extraoral force applied to the molars is theThe extraoral force applied to the molars is the
resultant force. This force has direction, in whichresultant force. This force has direction, in which
the line of action of a force is that line connectingthe line of action of a force is that line connecting
the point of origin of the force (head – or neckgearthe point of origin of the force (head – or neckgear
assembly hook) to the point of attachment (hook)assembly hook) to the point of attachment (hook)
on the outer bow.on the outer bow.
► The resultant force component acting on theThe resultant force component acting on the
banded molar tooth is the relationship of the line ofbanded molar tooth is the relationship of the line of
action to the center of resistance of the tooth.action to the center of resistance of the tooth.

►The center of resistance of the toothThe center of resistance of the tooth
remains constant.remains constant.
►The variables are, thereforeThe variables are, therefore
a) the distance of the line of action from thea) the distance of the line of action from the
center of resistance and,center of resistance and,
b) the inclination (or steepness) of the lineb) the inclination (or steepness) of the line
of action.of action.

DISTANCE OF THE LINE OFDISTANCE OF THE LINE OF
ACTION FROM THE CENTER OFACTION FROM THE CENTER OF
RESISTANCE.RESISTANCE.
C. Center of
resistance,
R. Center of rotation,
T. Line of action of
force

►This principle is easily analyzed by applyingThis principle is easily analyzed by applying
the simple formulathe simple formula
M = T x PM = T x P
M represent the moment producing theM represent the moment producing the
tippingtipping
T represent the tension (extraoral traction)T represent the tension (extraoral traction)
P represent the perpendicular distance fromP represent the perpendicular distance from
the center of resistance to the linethe center of resistance to the line
of action.of action.

C. Center of resistance, T. Tension (line of action of
force), P. Perpendicular distance, M. Moment

THE INCLINATION OF THE LINETHE INCLINATION OF THE LINE
OF ACTIONOF ACTION
►The inclination or steepness of the line ofThe inclination or steepness of the line of
action can be varied and is dependent uponaction can be varied and is dependent upon
(1) The point of origin of the force and(1) The point of origin of the force and
(2) The point of attachment of the force.(2) The point of attachment of the force.

► The point of origin ofThe point of origin of
the force is dependentthe force is dependent
upon the type ofupon the type of
assembly that is used.assembly that is used.
The numerous extraoralThe numerous extraoral
assemblies availableassemblies available
may be groupedmay be grouped
conveniently into threeconveniently into three
major categoriesmajor categories
P. Parietal, O. Occipital, C. Cervical

► The point ofThe point of
attachment of theattachment of the
force is the hook onforce is the hook on
the outer bow of thethe outer bow of the
extraoral assembly.extraoral assembly.
► Sagittal rectangle.Sagittal rectangle.
Theoretically, theTheoretically, the
outer bow hooksouter bow hooks
could be locatedcould be located
anywhere along APanywhere along AP
and VV, axes.and VV, axes.

►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, providedapplication of force to molar teeth, provided
the relationship of the point of attachmentthe relationship of the point of attachment
(outer bow hook) to the site of origin of the(outer bow hook) to the site of origin of the
force remains unaltered, namely, D1 = D2.force remains unaltered, namely, D1 = D2.
This contention applies only if it assumedThis contention applies only if it assumed
that the arms of the headgear are rigid.that the arms of the headgear are rigid.

►The points of attachment of the outer bowThe points of attachment of the outer bow
hooks are variable and may be altered to fithooks are variable and may be altered to fit
anywhere in the sagittal rectangle byanywhere in the sagittal rectangle by
1) varying the length of the outer bow,1) varying the length of the outer bow,
2) varying the angle between the inner and2) varying the angle between the inner and
outer bows, andouter bows, and
3) varying the length and the angle of the3) varying the length and the angle of the
outer bow.outer bow.

Distal translatory
molar movement
may be achieved
by adjusting the
length & angle of
the outer bow hook
so that the line of
action passes
through the center
of resistance of the
tooth C. Cervical
traction

Cervical traction.
Heavy stippling
depicts distal
crown tip. Light
stippling depicts
distal root tip.

Since the angles
and lengths of the
arms in the
diagram are
adjusted to be in
line with the line of
action, the molar
teeth will move
distally in a bodily
manner. O.
Occipital traction.

Occipital
traction. Heavy
stippling depicts
distal crown tip.
Light stippling
depicts distal root
tip.

Diagrammatic
illustration of
parietal type of
extraoral assembly
(P) acting on outer
bow hooks which are
adjusted in length
and angulation to
allow the line of
action to pass
through the center of
resistance of the
tooth, causing it to
translate. www.indiandentalacademy.com

Parietal traction.
Heavy stippling
depicts distal
crown tip. Light
stippling depicts
distal root tip.

► Distal force component.Distal force component. From a clinical pointFrom a clinical point
of view, in the most instances, the magnitude ofof view, in the most instances, the magnitude of
the distal component is of primary importance.the distal component is of primary importance.
► The distal force component is maximal when theThe distal force component is maximal when the
line of action is horizontal, rather than inclined,line of action is horizontal, rather than inclined,
and passes through the center of resistance of aand passes through the center of resistance of a
tooth.tooth.
► In this situation no extrusive or intrusiveIn this situation no extrusive or intrusive
components are present and the magnitude of thecomponents are present and the magnitude of the
distal force on the molars is equal to thedistal force on the molars is equal to the
magnitude of the force applied by the extraoralmagnitude of the force applied by the extraoral
assembly.assembly.

► The principles of molar extrusion (or intrusion) of theThe principles of molar extrusion (or intrusion) of the
distal force component are diagrammaticallydistal force component are diagrammatically
illustrated in Fig.illustrated in Fig.

► The distal, Extrusive, and intrusive effectThe distal, Extrusive, and intrusive effect
of various headgear assemblies on molarsof various headgear assemblies on molars
can be mathematically calculated.can be mathematically calculated.
► In analyzing the force system, aIn analyzing the force system, a
parallelogram of force diagram is used.parallelogram of force diagram is used.
► The classic formulas are:The classic formulas are:
1) Sin1) Sin αα == o ando and 2) Cos2) Cos αα = a= a
hh hh

Parallelogram of force diagram O, Opposite side
H, Hypotenuse, a. Adjacent side, a, Angle of
line of action. I. Intrusive force component, T.
Line of action of force D, Distal force
component.

►Application of the formula would be asApplication of the formula would be as
followsfollows
SinSin αα == II
TT
I = T SinI = T Sin αα

► If T was constant, the magnitude ofIf T was constant, the magnitude of
intrusion would be directlyintrusion would be directly
proportional to the Sinproportional to the Sinαα , viz., the, viz., the
steepness or inclination of the line ofsteepness or inclination of the line of
action of the force. The extrusiveaction of the force. The extrusive
component is directly related to thecomponent is directly related to the
steepness of the line of action. Thesteepness of the line of action. The
greater the angle or the steeper thegreater the angle or the steeper the
inclination of the line of action, theinclination of the line of action, the
greater the extrusive effect on thegreater the extrusive effect on the
tooth.tooth.

► If angle “If angle “α”α” was constant. I. would bewas constant. I. would be
directly proportional to T. In otherdirectly proportional to T. In other
words, if the angle of the line of actionwords, if the angle of the line of action
of the force was constant, theof the force was constant, the
magnitude of the intrusive force Imagnitude of the intrusive force I
would be directly proportional to thewould be directly proportional to the
magnitude of the applied force.magnitude of the applied force.

►The sum, therefore, the amount ofThe sum, therefore, the amount of
distal or intrusive (or extrusive) forcedistal or intrusive (or extrusive) force
that is clinically applied to molars withthat is clinically applied to molars with
the use of extraoral appliances isthe use of extraoral appliances is
dependent upon the steepness of thedependent upon the steepness of the
line of action of the extraoral force. Theline of action of the extraoral force. The
steeper the line of action, the greatersteeper the line of action, the greater
the intrusive (or extrusive) force.the intrusive (or extrusive) force.

►A horizontal line of action exertsA horizontal line of action exerts
maximal distal force to molars with nomaximal distal force to molars with no
extrusive or intrusive force. As the lineextrusive or intrusive force. As the line
of action steepens, so do the extrusiveof action steepens, so do the extrusive
or intrusive forces at the expense ofor intrusive forces at the expense of
reducing the distal force component toreducing the distal force component to
the molars.the molars.

Coronal PlaneCoronal Plane
►In the coronal plane, molar teeth can beIn the coronal plane, molar teeth can be
moved vertically (intruded or extruded) and /moved vertically (intruded or extruded) and /
or laterally or medially.or laterally or medially.

Transverse PlaneTransverse Plane
► In the transverse plane teeth canIn the transverse plane teeth can
be moved distally and / or laterally.be moved distally and / or laterally.

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

HEAD GEARHEAD GEAR
►Head gears are the most commonly usedHead gears are the most commonly used
extraoral orthopedic appliances. They areextra- oral orthopedic appliances. They are
used during the growth period to intercept orused during the growth period to intercept or
correct certain skeletal malocclusions ascorrect certain skeletal malocclusions as
well as to distalize the maxillary dentition orwell as to distalize the maxillary dentition or
maxilla itself. Head gears also form one ofmaxilla itself. Head gears also form one of
the important adjuncts to control or gainthe important adjuncts to control or gain
anchorage.anchorage.

HISTORICAL PERSPECTIVEHISTORICAL PERSPECTIVE
Use of extraoral forces to modify the growth ofUse of extraoral forces to modify the growth of
the maxilla has a long history, dating back tothe maxilla has a long history, dating back to
Kingsley and Angle in the 19th century. Both usedKingsley and Angle in the 19th century. Both used
occipital headgears to retract and intrude maxillaryoccipital headgears to retract and intrude maxillary
incisors.incisors.
Interest in extraoral traction diminished in theInterest in extraoral traction diminished in the
first half of the 20th century, especially with thefirst half of the 20th century, especially with the
increased popularity of intermaxillary elastics.increased popularity of intermaxillary elastics.
Interest in headgear was revived by Oppenheim &Interest in headgear was revived by Oppenheim &
later by Kloehn who recommended the applicationlater by Kloehn who recommended the application
of extra-oral forces for the mass distal movementof extra-oral forces for the mass distal movement
of teethof teeth

Components of HeadgearComponents of Headgear
The head gear - face bow assembly hasThe head gear - face bow assembly has
three main componentsthree 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 the extra-transmitting the extra-
oral forces on to theoral forces on to the
posterior teeth. Theposterior teeth. The
face bow consists offace bow consists of
outer bow, inner bowouter bow, inner bow
and the junction .and the junction .
Fig.1. Facebow (A) Outer bow (B)
Inner bow (C) Junction

Types of facebowTypes of facebow
Along with a cervical strap, two types of facebowsAlong with a cervical strap, two types of facebows
can be usedcan 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 force facebowAccording to origin of force facebow
divided into as followsdivided into as follows
► Cervical-pull facebowCervical-pull facebow
► High-pull facebowHigh-pull facebow
► Combi facebowCombi facebow
► Asymmetric facebowAsymmetric facebow

Bending of Facebow:Bending of Facebow:

Placement of Facebow:Placement of Facebow:
►In a correctly fitted appliance, the solderedIn a correctly fitted appliance, the soldered
joint should comfortably placed between thejoint should comfortably placed between the
lips. When the elastic strap is put on thelips. When the elastic strap is put on the
outer bow should not stick into the patientsouter bow should not stick into the patients
cheeks. The inner bow should fit passivelycheeks. The inner bow should fit passively
into the headgear tubes if it does not thereinto the headgear tubes if it does not there
will be loose bandswill be loose bands

► Buccal tubesBuccal tubes are positioned either gingivally orare positioned either gingivally or
occlusally on the molar bracket.occlusally on the molar bracket.
► The outer bowThe outer bow ends anteriorly to the ears andends anteriorly to the ears and
should be 5 to 10mm from the cheeks. In almostshould be 5 to 10mm from the cheeks. In almost
every case, the outer bow is positioned in theevery case, the outer bow is positioned in the
horizontal plane parallel to and even with the innerhorizontal plane parallel to and even with the inner
bow.bow.

► Inner bow;Inner bow; Proper adjustment of the inner bow willProper adjustment of the inner bow will
allow the wire to slide in and out of the headgearallow the wire to slide in and out of the headgear
tubes easily when the posterior strap is nottubes easily when the posterior strap is not
attached.attached.
► Adjustments to the inner bow can be made in sixAdjustments to the inner bow can be made in six
directions: bucco-lingually, superior-inferiorly, anddirections: bucco-lingually, superior-inferiorly, and
antero-posteriorly.antero-posteriorly.
► The bow should be in a passive position betweenThe bow should be in a passive position between
the two lipsthe two lips

►The force element:The force element:
It is that part of the assembly whichIt is that part of the assembly which
provides the force to bring about theprovides the force to bring about the
desired effect. This may comprise ofdesired effect. This may comprise of
springs, elastics and other stretchablesprings, elastics and other stretchable
materials. The force element connectsmaterials. The force element connects
the face bow to the head cap or neckthe face bow 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 the rigidThe appliance takes anchorage from the rigid
bones of the skull or from the back of the neck bybones of the skull or from the back of the neck by
means of a head cap or neck strap or a combinationmeans of a head cap or neck strap or a combination
of the two. The selection of this depends upon theof the two. The selection of this depends upon the
individual patient needs.individual patient needs.

Design of Head gearDesign of Head gear

Types of Head gears:Types of Head gears:
► J-Hook Headgear:J-Hook Headgear:
► Variable–Pull Headgear:Variable–Pull Headgear:

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

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

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

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

Other typesOther types
► Interlandi Type:Interlandi Type:
► AsymmetricAsymmetric
Headgear:Headgear:

Selection of Headgear TypeSelection of Headgear Type
►There are three major decisions to be madeThere are three major decisions to be made
in the selection of headgear.in the selection of headgear.
1)1) The headgear anchorage locationThe headgear anchorage location
2) How the headgear is to be attached to2) How the headgear is to be attached to
the dentitionthe dentition
3) whether bodily movement or tipping of3) whether bodily movement or tipping of
the teeth or maxilla is desired.the teeth or maxilla is desired.

Dental & Skeletal Changes WithDental & Skeletal Changes With
Different Head GearsDifferent Head Gears
► Effect on dentitionEffect on dentition

► Effect on MaxillaEffect on Maxilla

Effects of Cervical head gearsEffects of Cervical head gears
►Cervical pull force vector inferior to bothCervical pull force vector inferior to both
centers of resistancecenters of resistance

►Cervical pull force vector passing betweenCervical pull force vector passing between
the centers of resistancethe centers of resistance

► If cervical head gear force to the maxilla moves itIf cervical head gear force to the maxilla moves it
downward, mandibular growth will be expresseddownward, mandibular growth will be expressed
more vertically and less horizontally, impeding themore vertically and less horizontally, impeding the
successful correction of a Class II problem.successful correction of a Class II problem.

Effects of occipital head gearsEffects of occipital head gears
►occipital pull force vector inferior to bothoccipital pull force vector inferior to both
centers of resistancecenters of resistance

►occipital pull force vector passing betweenoccipital pull force vector passing between
the centers of resistancethe centers of resistance

Clinical Application of HeadClinical Application of Head
GearGear
►There are four main uses of headgear forceThere are four main uses of headgear force
in contemporary treatment of Class IIin contemporary treatment of Class II
malocclusions: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 occlusal plane.4. Controlling the cant of the occlusal plane.

Treatment IntensityTreatment Intensity
►Heavy forces versus light forcesHeavy forces versus light forces
►Continuous force versus intermittent forceContinuous force versus intermittent force
►Early treatment versus late treatment.Early treatment versus late treatment.

►The majority of authors believe that theThe majority of authors believe that the
amount of force applied to maxilla by extraamount of force applied to maxilla by extra
oral traction should lie between 400-800gmoral traction should lie between 400-800gm
►Graber advocates a force application ofGraber advocates a force application of
more than 400gm for only 10 – 12 hours/daymore than 400gm for only 10 – 12 hours/day
to produce significant basal bone effectsto produce significant basal bone effects
and to allow the body to restore normaland to allow the body to restore normal
circulation to the periodontium for healingcirculation to the periodontium for healing
purpose.purpose.

Treatment TimingTreatment Timing
►Orthopedics has shown us that pressure onOrthopedics has shown us that pressure on
bone causes it to change.bone causes it to change.
►Pressure on growing bone has even morePressure on growing bone has even more
dramatic results.dramatic results.
►Thus, to effect maximum morphologicThus, to effect maximum morphologic
changes in bone, pressure should bechanges in bone, pressure should be
applied during a period of rapid growth.applied during a period of rapid growth.

►Woodside was able to demonstrate threeWoodside was able to demonstrate three
possible periods of accelerated growth.possible periods of accelerated growth.
The peak period in boys are judged to beThe peak period in boys are judged to be
6½yrs , 9yrs and 15yrs and girls 6yrs.6½yrs , 9yrs and 15yrs and girls 6yrs.
7½yrs and 12yrs.7½yrs and 12yrs.
►Graber orthopedic guidance potential existsGraber orthopedic guidance potential exists
from birth to 12 – 13yrs in girls and almostfrom birth to 12 – 13yrs in girls and almost
18yrs in boys.18yrs in boys.

Safety MeasuresSafety Measures
►Of major concern to orthodontistsOf major concern to orthodontists
everywhere have been a few injuries fromeverywhere have been a few injuries from
extra oral appliances that could have beenextra oral appliances that could have been
avoided with proper careavoided with proper care
► The majority of incidence seems to occurThe majority of incidence seems to occur
from accidental disengagement.from accidental disengagement.

►Unfortunately, no method can confirmUnfortunately, no method can confirm
absolute safety, but because Head gearsabsolute safety, but because Head gears
are able to cause some injuries which canare able to cause some injuries which can
have irreversible consequences for thehave irreversible consequences for the
clinician it would seem wise to use a safetyclinician it would seem wise to use a safety
face bow together a safety release systemface bow together a safety release system
to improves the safety margin of Headto improves the safety margin of Head
Gears.Gears.

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 vertical development andInhibition of maxillary vertical development and
even intrusion can be brought about.even intrusion can be brought about.
► Limited clockwise rotation of palate occurs.Limited clockwise rotation of palate occurs.
► Overbite and especially overjet can be decreasedOverbite and especially overjet can be decreased

Head gear effectHead gear effect
►In functional appliance therapy the mandibleIn functional appliance therapy the mandible
is held forward, and the elastic stretch of softis held forward, and the elastic stretch of soft
tissues produces a reactive effect on thetissues produces a reactive effect on the
structures that hold it forward . The softstructures that hold it forward . The soft
tissue elasticity creates a restraining forcetissue elasticity creates a restraining force
on the forward growth of maxilla called headon the forward growth of maxilla called head
gear effect.gear effect.

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

►The use of an activator with head gear wasThe use of an activator with head gear was
shown by Pfeiffer and Grobety (1972) toshown by Pfeiffer and Grobety (1972) to
reduce the duration of treatmentreduce the duration of treatment
significantly.significantly.

ACTIVATOR - HEADGEARACTIVATOR - HEADGEAR
Orthodontic and orthopedic effects of Activator,Orthodontic and orthopedic effects of Activator,
Activator-HG combination, and Bass appliances:Activator-HG combination, and Bass appliances:
A comparative study.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-pull headThe use of combined activator-high-pull head
gear appliance has been recommended as agear appliance has been recommended as a
means of reducing vertical and sagittal maxillarymeans of reducing vertical and sagittal maxillary
displacement, achieving autorotation, anddisplacement, achieving autorotation, and
increasing forward displacement of the mandible.increasing forward displacement of the 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 sagittal skeletal1. Greater improvement in the sagittal skeletal
relationship (ANB angle) was obtained in both therelationship (ANB angle) was obtained in both the
Bass and ACHG groups than in the ActivatorBass and ACHG groups than in the Activator
group.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 side effectseffective in the control of the unwanted side effects
(proclination of the lower incisors, retroclination of(proclination of the lower incisors, retroclination of
the upper incisors).the upper incisors).
► 3. Unfavorable labial tipping of the lower incisors3. Unfavorable labial tipping of the lower incisors
was prevented also with the ACHG appliance.was prevented also with the ACHG appliance.

FRANKEL – HEAD GEARFRANKEL – HEAD GEAR
The modified function regulator appears to offerThe modified function regulator appears to offer
the following advantages in combining functionalthe following advantages in combining functional
jaw orthopedics with directional force headgear injaw orthopedics with directional force headgear in
the early comprehensive treatment of long facethe early comprehensive treatment of long face
patients: By Allbert H. Owenpatients: By Allbert H. Owen
► 1. The vertical dimension or anterior facial height1. The vertical dimension or anterior facial height
(ANS-Me) can be held constant or even(ANS-Me) can be held constant or even
decreased through the holding or intrusion of thedecreased through the holding or intrusion of the
upper molars.upper molars.

►2. Although no condylar growth was2. Although no condylar growth was
demonstrable in this study, there is thedemonstrable in this study, there is the
potential for increased mandibular growth. Itpotential for increased mandibular growth. It
may be limited to cooperative patients duringmay be limited to cooperative patients during
growth spurts.growth spurts.
►3. There appears to be an improvement in3. There appears to be an improvement in
function of the circum- and perioral muscles.function of the circum- and perioral muscles.
Upper lip integrity appears to be protected inUpper lip integrity appears to be protected in
spite of overjet correction or incisorspite of overjet correction or incisor
retraction.retraction.
►4. The significant lateral expansion may4. The significant lateral expansion may
reduce the need for extractions.reduce the need for extractions.

THE FACIAL MASKTHE FACIAL MASK
► A reverse pull head gearA reverse pull head gear
basically consists of a rigidbasically consists of a rigid
extra-oral framework whichextra-oral framework which
takes anchorage from thetakes anchorage from the
chin or forehead or both forchin or forehead or both for
the anterior traction of thethe anterior traction of the
maxilla using extra-oralmaxilla using extra-oral
elastics which generateelastics which generate
large amounts of forcelarge amounts of force
upto 1 kg or more.upto 1 kg or more.

►Although the facial mask was developedAlthough the facial mask was developed
over 100 years ago.over 100 years ago. HickhamHickham claims he wasclaims he was
the first to use a reverse headgear.the first to use a reverse headgear.
However, this modality was made popularHowever, this modality was made popular
byby DelaireDelaire around the same time.around the same time.

►This approach was used infrequently untilThis approach was used infrequently until
reintroduced byreintroduced by DelaireDelaire in the late 1960s forin the late 1960s for
the treatment of cleft patients.the treatment of cleft patients.
► Interest in the facial mask in the UnitedInterest in the facial mask in the United
States later was stimulated byStates later was stimulated by PetitPetit throughthrough
his studies conducted at Baylor University.his studies conducted at Baylor University.

COMPONENTS OFCOMPONENTS OF
ORTHOEDIC FACIAL MASKORTHOEDIC FACIAL MASK
THERAPYTHERAPY
The component of facial mask applianceThe component of facial mask appliance
►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 obtain anchorageMost protraction head gears obtain anchorage
from the chin as well as the forehead.from the chin as well as the forehead.
► The chin cup is used to take anchorage from theThe chin cup is used to take anchorage from the
chin area. It is usually connected to the rest of thechin area. It is usually connected to the rest of the
face mask assembly by means of metal rods.face mask assembly by 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 the patient'sfabricated from an impression of the patient's
genial region.genial region.

►Forehead capForehead cap:: The forehead support orThe forehead support or
cap or strap is used to derive anchoragecap or strap is used to derive anchorage
from the forehead.from the forehead.
►Metal frame:Metal frame: The main component of aThe main component of a
face mask assembly is the metal frame- Itface mask assembly is the metal frame- It
connects the various components such asconnects the various components such as
the chin cup and forehead cap. It also hasthe chin cup and forehead cap. It also has
provision to receive elastics from theprovision to receive elastics from the
intraoral appliance. The design of the metalintraoral appliance. 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 protraction device is aThe most common type of protraction device is a
multibanded appliance with rigid wire. Tractionmultibanded appliance with rigid wire. Traction
hooks are placed either in the molar or premolarhooks are placed either in the molar or premolar
region. McNamara advocates a banded R.M.E.region. McNamara advocates a banded R.M.E.
along with the protraction device which more oralong with the protraction device which more or
less resembles the banded Herbst appliance.less resembles the banded Herbst appliance.

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 the maxillarystretching elastics from the hooks on the maxillary
splint to the crossbow of the facial masksplint to the crossbow of the facial mask

Types of reverse pull headTypes of reverse pull head
geargear
► 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 patient having aIt can be used in a growing patient having a
prognathic mandible and a retrusive maxilla.prognathic mandible and a retrusive maxilla.
It aids in pulling the maxillary structuresIt aids in pulling the maxillary structures
forward and pushing the mandibularforward and pushing the mandibular
structures backward.structures backward.
► It can be used for bending the condylarIt can be used for bending the condylar
neck for stimulating temporomandibular jointneck for stimulating temporomandibular joint
adaptations to posterior displacement of theadaptations to posterior displacement of the
chin.chin.

► It can also be used for selectiveIt can also be used for selective
rearrangement of the palatal shelves in cleftrearrangement of the palatal shelves in cleft
patients.patients.
► It can be used in correction of post-surgicalIt can be used in correction of post-surgical
relapse after osteotomies (or uncontrolledrelapse after osteotomies (or uncontrolled
post-surgical adaptations).post-surgical adaptations).
► It can be used to treat certain accessoryIt can be used to treat certain accessory
problems associated with nose morphologyproblems associated with nose morphology
such as lateral deviationssuch as lateral deviations

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.www.indiandentalacademy.com

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

CHIN CUPCHIN CUP
► The chin cup or the chin cap as it is sometimesThe chin cup or the chin cap as it is sometimes
referred to is an extra-oral orthopedic device thatreferred to is an extra-oral orthopedic device that
covers the chin and is connected to a head gear. Itcovers the chin and is connected to a head gear. It
is used to restrict the forward and downwardis used to restrict the forward and downward
growth of the mandiblegrowth of the mandible

Components of Chin Cup:Components of Chin Cup:
►The chin cup-face bow assembly consists ofThe chin cup-face bow assembly consists of
a chin cup that covers the chin, a head capa chin cup that covers the chin, a head cap
and an adjustable elastic strap that connectsand an adjustable elastic strap that connects
the chin cup with the head cap.the chin cup with the head cap.

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

Occipital Chin Cup :Occipital Chin Cup :
►The occipital-pull chin cup is the moreThe occipital-pull chin cup is the more
frequently used type of chincup treatment forfrequently used type of chincup treatment for
Class III malocclusion. This chin cup isClass III malocclusion. This chin cup is
indicated in instances of mild to moderateindicated in instances of mild to moderate
mandibular prognathism and is best initiatedmandibular prognathism and is best initiated
during the late deciduous or early mixedduring the late deciduous or early mixed
dentition.dentition.

Vertical Pull Chin Cup :Vertical Pull Chin Cup :
► Vertical-pull chin cups are applicable not only inVertical-pull chin cups are applicable not only in
Class III patients with anterior open bite tendenciesClass III patients with anterior open bite tendencies
but also can be used in patients who have anbut also can be used in patients who have an
increased anterior vertical dimension.increased anterior vertical dimension.
► Pearson hasPearson has rereported that the use of a vertical-pullported that the use of a vertical-pull
chin cup can result in a decrease in the mandibularchin cup can result in a decrease in the mandibular
plane and gonial angles and an increase inplane and gonial angles and an increase in
posterior facial height, in comparison to the growthposterior facial height, in comparison to the growth
of untreated individuals.of untreated individuals.

Treatment effectTreatment effect
The orthopedic effects of a chin cup on theThe orthopedic effects of a chin cup on the
mandible includemandible include
►(1) redirection of mandibular growth(1) redirection of mandibular growth
vertically,vertically,
►(2) backward repositioning (rotation) of the(2) backward repositioning (rotation) of the
mandible, andmandible, and
►(3) remodeling of the mandible with closure(3) remodeling of the mandible with closure
of gonial angle.of gonial angle.

There are two main
approaches to chin
cup therapy, as
shown
diagrammatically
here; they force
aimed directly at the
condylar area, or
lighter force 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.www.indiandentalacademy.com

Force Magnitude andForce Magnitude and
Direction :Direction :
►At the time of appliance delivery a force ofAt the time of appliance delivery a force of
150-300 grams per side is used. Over the150-300 grams per side is used. Over the
next two months the force is graduallynext two months the force is gradually
increased to 450-700 grams per sideincreased to 450-700 grams per side

Treatment Timing & DurationTreatment Timing & Duration
► Patient with mandibular excess can usually bePatient with mandibular excess can usually be
recognized in the primary dentition despite the factrecognized in the primary dentition despite the fact
that the mandible appears retrognathic in the earlythat the mandible appears retrognathic in the early
years for most children.years for most children.
► Evidence exists that treatment to reduceEvidence exists that treatment to reduce
mandibular protrusion is more successful when it ismandibular protrusion is more successful when it is
started in the primary or early mixed dentition.started in the primary or early mixed dentition.
► The treatment time varies from 1 year to as long asThe treatment time varies from 1 year to as long as
4 years depending on the severity of the original4 years depending on the severity of the original
malocclusion.malocclusion.

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

CONCLUSIONCONCLUSION
► Extraoral orthopedic appliance hasExtraoral orthopedic appliance has
proved to be a dependable method of classproved to be a dependable method of class
II and class III correction for over 100 yearsII and class III correction for over 100 years
and this treatment adjunct is used withand this treatment adjunct is used with
varying frequency world wide.varying frequency world wide.
► The major “Achilles heal” this method is hasThe major “Achilles heal” this method is has
with other methods that involve participationwith other methods that involve participation
of the patient in the treatment process, isof the patient in the treatment process, is
patient co-operation.patient co-operation.

►When the extra oral orthopedic appliance isWhen the extra oral orthopedic appliance is
prescribed for patient who is compliant,prescribed for patient who is compliant,
effective and efficient treatment is the result.effective and efficient treatment is the result.
In the non co-operative patient howeverIn the non co-operative patient however
alternative methods of class II and class IIIalternative methods of class II and class III
correction are indicated.correction are indicated.

REFERENCESREFERENCES
► ARMSTRONG. M.M.: Controlling the magnitude direction andARMSTRONG. M.M.: Controlling the magnitude direction and
duration of extra oral force. Am. J. Orthod. 59; 277. 1971.duration of extra oral force. Am. J. Orthod. 59; 277. 1971.
► BANKS, and READ: An investigation into the reliabilities of the timingBANKS, and READ: An investigation into the reliabilities of the timing
headgear. Brit .J. Orthod. 14; 263, 1987.headgear. Brit .J. Orthod. 14; 263, 1987.
► BAUMRIND. S and KORN, E.L.: Patterns of change in mandibularBAUMRIND. S and KORN, E.L.: Patterns of change in mandibular
and facial shape associated with the use of forces to retract theand facial shape associated with the use of forces to retract the
maxilla Am. J. ORTHOD. 08; 17, 32, 1981.maxilla Am. J. ORTHOD. 08; 17, 32, 1981.
► BEGG. P.R. and KESLING P.C.: Begg Orthodontic Technique andBEGG. P.R. and KESLING P.C.: Begg Orthodontic Technique and
Theory. W.B. Saunders Co. 1971.Theory. W.B. Saunders Co. 1971.
► CLARK. W.J.: The twin block technique. Am. J. Orthod. 93; 1, 1988.CLARK. W.J.: The twin block technique. Am. J. Orthod. 93; 1, 1988.
► CHACONAS. S.J.: Orthodontics Post-graduate dental handbook.CHACONAS. S.J.: Orthodontics Post-graduate dental handbook.
Vol-10. John Wright 1982.Vol-10. John Wright 1982.
► CHACONAS. S.J.: CAPUTO A.A. et al: The effect of orthopedicCHACONAS. S.J.: CAPUTO A.A. et al: The effect of orthopedic
forces on the cranio facial complex utilizing (forces) cervical andforces on the cranio facial complex utilizing (forces) cervical and
headgear appliances. Am. J. Orthod. 69; 527, 1976.headgear appliances. Am. J. Orthod. 69; 527, 1976.

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

► Mc NAMARA. L.A. Jr: Neuromuscular and skeletal adaptations to alteredMc NAMARA. L.A. Jr: Neuromuscular and skeletal adaptations to altered
orofacial function. Monograph – 1, Craniofacial growth series. Ann Arbor,orofacial function. Monograph – 1, Craniofacial growth series. Ann Arbor,
Michigan. 1972.Michigan. 1972.
► MERRIFIELD. L.L. and CROSS. J.J.: Directional forces. Am. J. Orthod.MERRIFIELD. L.L. and CROSS. J.J.: Directional forces. Am. J. Orthod.
57;4355, 1971.57;4355, 1971.
► MAGNI, FRANCO; The activated face-bow simple safety extra-oral traction.MAGNI, FRANCO; The activated face-bow simple safety extra-oral traction.
Am. J. Orthod. 75; 152, 1979.Am. J. Orthod. 75; 152, 1979.
► NIKOLAI. R.J.: An optimum orthodontic force theory as applied for canineNIKOLAI. R.J.: An optimum orthodontic force theory as applied for canine
retraction. Am. J. Orthod. 68; 290, 1975.retraction. Am. J. Orthod. 68; 290, 1975.
► PETROVIC. A; STUTZMAN. J. and OUDET. C.L.: Control processes in thePETROVIC. A; STUTZMAN. J. and OUDET. C.L.: Control processes in the
postnatal growth of condylar cartilage. In Mc Namara J.A. Monograph – 4.postnatal growth of condylar cartilage. In Mc Namara J.A. Monograph – 4.
Craniofacial growth series. Ann Arbon, Michigan, 1975.Craniofacial growth series. Ann Arbon, Michigan, 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? In Carlson. D.S.repositioning the best procedure to elicit over lengthening? In Carlson. D.S.
and Ribben, editors: Craniofacial biology, Monograph – 10, Craniofacialand Ribben, editors: Craniofacial biology, Monograph – 10, Craniofacial
growth series. Ann Arbon. Michigan. 1981.growth series. Ann Arbon. Michigan. 1981.
► PFEIFER. J.P. and CROBETY. D.: The Class II malocclusion: differentialPFEIFER. J.P. and CROBETY. D.: The Class II malocclusion: differential
diagnosis and clinical application of activators, extra oral forces and fixeddiagnosis and clinical application of activators, extra oral forces and fixed
appliances. Am. J. Orthod. 68; 499, 1975.appliances. Am. J. Orthod. 68; 499, 1975.
► POULTION. D.R.: The influence of extra oral traction. Am. J. Orthod. 53;8,POULTION. D.R.: The influence of extra oral traction. Am. J. Orthod. 53;8,
1967.1967.
► PROFFIT. W.R.: P.P. 211 Contemporary orthodontics, C.V. Mosby Co. 1986.PROFFIT. W.R.: P.P. 211 Contemporary orthodontics, C.V. Mosby Co. 1986.

► RICKETTS. R.M.: The influence of orthodontic treatment in facialRICKETTS. R.M.: The influence of orthodontic treatment in facial
growth and development. Angle Orthod. 30; 103, 1960.growth and development. Angle Orthod. 30; 103, 1960.
► RICKETTS. R.M.: Mechanisms of mandibular growth. In Mc Namara.RICKETTS. R.M.: Mechanisms of mandibular growth. In Mc Namara.
J.A. editor: Monograph – 4, Craniofacial growth series. Ann Arbor.J.A. editor: Monograph – 4, Craniofacial growth series. Ann Arbor.
Michigan – 1975.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 on Headgear. J. Clin.ROOT. T.I.: JOC Interviews: Dr. Terrel. L. Root on Headgear. J. Clin.
Orthod. 90. 20. 1975.Orthod. 90. 20. 1975.
► ROOT. R.H.: Treatment mechanics for the straight wire appliance.ROOT. R.H.: Treatment mechanics for the straight wire appliance.
Orthodontics – current principles and practice. Graber and Swain.Orthodontics – current principles and practice. Graber and Swain.
C.V. Mosby. Co. 1985.C.V. Mosby. Co. 1985.
► SABDYSKY. Cephalometric evaluation of the Kloehn type of cervicalSABDYSKY. Cephalometric evaluation of the Kloehn type of cervical
traction. Am. J. Orthod. 51; 262, 1965.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 Class IITEUSHER. U.M.: A growth related concept for skeletal Class II
treatment. Am. J. Orthod. 74; 258, 1978.treatment. Am. J. Orthod. 74; 258, 1978.
► THUROW. R.C. Craniomaxillary orthopedic correction with enmasseTHUROW. R.C. Craniomaxillary orthopedic correction with enmasse
dental control. Am. J. Orthod. 68; 601, 1975.dental control. Am. J. Orthod. 68; 601, 1975.
► THUROW. P.: Atlas of orthodontic principles. C.V. Mosby, Co. 1970.THUROW. P.: Atlas of orthodontic principles. C.V. Mosby, Co. 1970.

► WIESLANDER. L.: The effect of force of craniofacial development.WIESLANDER. L.: The effect of force of craniofacial development.
Am. J. Orthod. 65;531, 1974.Am. J. Orthod. 65;531, 1974.
► WIESLANDER. L.: J.C.O/Interviews on dentofacial orthopedicsWIESLANDER. L.: J.C.O/Interviews on dentofacial orthopedics
Headgear Herbst treatment in the mixed dentition. J. Clin. Orthod. 18;Headgear Herbst treatment in the mixed dentition. J. Clin. Orthod. 18;
551, 1984.551, 1984.
► WIESLANDER. L.: Intensive treatment of severe Class IIWIESLANDER. L.: Intensive treatment of severe Class II
malocclusion with a headgear – Herbst appliance. Am. J. Orthod.malocclusion with a headgear – Herbst appliance. Am. J. Orthod.
86;1, 1984.86;1, 1984.
► WORMS. F.W. et al: A concept and classification of rotation andWORMS. F.W. et al: A concept and classification of rotation and
extra oral force systems. Angle Orthod. 43; 384, 1973.extra oral force systems. Angle Orthod. 43; 384, 1973.
► GRABER. T.M.: Orthodontics principles and practice. Philadelphia:GRABER. T.M.: Orthodontics principles and practice. Philadelphia:
W.B. Saunders Co.; 2001.W.B. Saunders Co.; 2001.
► PROFFIT. W.R.: Contemporary orthodontics. St. Louis: C.V. MosbyPROFFIT. W.R.: Contemporary orthodontics. St. Louis: C.V. Mosby
Company; 2000.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: Mosby – Wolte;CLARK. W.J.: Twin Block functional therapy. London: Mosby – Wolte;
1995.1995.
► GRABER. T.M., VANARSDALL R.L.: Orthodontics current principlesGRABER. T.M., VANARSDALL R.L.: Orthodontics current principles
and techniques. St. Louis: Mosby; 2000.and techniques. St. Louis: Mosby; 2000.

Thank youThank you

Dentofacialorthopedics

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (20)

Similar to Dentofacialorthopedics

Similar to Dentofacialorthopedics (20)

More from Indian dental academy

More from Indian dental academy (20)

Recently uploaded

Recently uploaded (20)

Dentofacialorthopedics

Editor's Notes