Extraoral appliances

 Introduction
 Principles
 classification
 History
 Types of head gear
 uses
 Biomechanics of headgear
 Clinical applications
 Effect of treatment with headgears
 Protraction face mask
 Types of facemask
 Biomechanics of facemask

 Extraoral appliances or orthopedic
appliances are used to modify the
growth of maxilla and mandible using
extraoral forces.
They are appliance’s that provide a
means of applying anterior, posterior or
vertical directed forces to the dentition
and skeletal complex from an extra-oral
source

• There are essentially 3 alternatives for treating
any skeletal malocclusion –
• (i) growth modification
• (ii) dental camouflage
• (iii) orthognathic surgery
• Growth modification should be opted
wherever applicable because this precludes
the need for both tooth extraction and
surgery.

• Goal of growth modification is to alter the
unacceptable skeletal relationships by modifying
the patients remaining facial growth to favorably
change the size or position of the jaws.
• There are 3 types of orthodontic appliances that can
be used for modifying the growth of
maxilla/mandible-
(i) orthopedic appliances
(ii) functional appliances
(iii) inter arch elastic traction
• This seminar discusses the essential aspects of
orthopedic appliances.

• There are 2 types of forces used in
orthodontics-
1) orthodontic force – when applied brings
about dental change. They are light forces
( 50-100 gm) bringing about tooth
movement.
2) orthopedic force – when applied brings
about the skeletal changes. They are heavy
forces ( 300-500gm) that bring about
changes in the magnitude & direction of
bone growth.

 Basis of orthopedic appliance therapy
resides in the use of intermittent forces
of very high magnitude
 Such heavy forces when directed to
the basal bone via teeth tend to alter
the magnitude & direction of the jaws
by modifying the pattern of bone
apposition at periosteal sutures &
growth sites

1) Magnitude of force –
• Extra oral forces of much greater
magnitude, in excess of 400gms per side
is required to bring about skeletal
changes.
• Most orthopedic appliances employ
forces in the range of 400-600 gm per
side to maximize skeletal effect

 Kloehn suggested the use of ¾-3pounds of force.
 armstrong and watson showed the use of 2-6 pounds of
force, would bring about skeletal relationship changes
 Closson prescribed light and intermittent forces on the molar
.he felt , the younger the patient the lesser the pressure to be
applied.
 Baldridge when doing clinical tests on the efficiency of the
appliance carried out 1-2 pounds of force
 Rickkets( 1979) force of 150 grms was appropriate for
extraoral retraction in adults and children.500 gm was
required for orthopeadic change
Armstrong, M. M.: Controlling the magnitude, direction, and duration of extraoral force, AM.
J. ORTHOD.59: 217-243, 1971.
Watson, W. G.: A computerized appraisal of the high-pull face bow, AM. J. ORTHOD. 62: 561,
1972.
Kloehn, S. J.: Guiding alveolar growth and eruption of teeth to reduce treatment time and
produce a more balanced denture and face, Angle Orthod. 17: 10.33. 1947.
Baldridge, unilatral traction with headcap, angle orthod .31:63:68,1961

 McLaughin , Bennet and Trevisi (2001)
recommended a force level of 250- 350
to provide anchorage for fixed
appliances.
 In combination system- 100grm cervical
pull with 150grm high pull for
anchorage.

2) Duration of force –
• Orthopedic changes are best produced
by employing intermittent heavy forces.
• Intermittent forces of 12-14 hours
duration per day appear to be effective
in producing orthopedic changes.
• An intermittent heavy force is less
damaging to the teeth and
periodontium than a continuous heavy
force.

 Poulton stressed on the point that the appliance
should be worn atleast 12 hours a day
 Armstone and watson suggested 22- 24 hours a day
 Kloehn suggested 12-14 hours a day.
Poulton, changes in class II malocclusion with and without
headgear therapy Angle orthod 29: 232-250.1950

Direction of force –
• Orthopedic force should be applied in the
appropriate direction to have a maximum
skeletal effect.
• The desired changes are best achieved when
the line of force passes through the center of
resistance of the skeletal structures to be moved.
• The force direction or force vector should be
decided depending on the clinical needs

4) Age of the patient –
 It is advisable to begin orthopedic appliance
therapy while patient is still in the mixed dentition
period, to make most of the active growth
occurring prepubertal growth spurt.
 Treatment may have to be continued until the
completion of adolescent growth, so as to
prevent relapse caused by the re-expression of
patients fundamental growth pattern after
cessation of orthopedic therapy

 Kloehn and closson preferd to commence
treatment in the early mixed dentition
stage, at the age of 4- 6 years.
 Lucchesse (1960), mossman and
hackensack, parker put emphasis on
starting the treatment before the pubertal
growth spurt. 10-14 years
 Graber, block and Fisher suggested
treatment in the mixed dentition itself
because incidence of root resorption was
lowered in this stage of dentition.

 In contrast to all these suggestion concerning
mixed dentition, Fletcher in Dental practitioner,
stated “the arrival of the full dentition provides
the orthodontist with firmer and more extensive
anchorage against which multiple tooth
movements can be carried out.”
Fletcher, the age factor In orthodontics, 1958
Lucchese, indications for the use of orthodontic appliances exerting
extra-oral force, 1960
Graber,Orthodontic forces- facts and fallacies. Am.j Orthod, 1955
Block, Headgear-modifications and admonition,1954

The following are the commonly used
orthopeadic appliances.
 Head gear
 Reverse pull facial mask
 Chin cup

 Weinberger in his book “Orthodontic review ,
evolution and progress” reported J.S Gunnel used
the occipital anchorage at around 1822-23
 The head gear was popularised for retraction of
upper protruding incisors by Norman kingsley in
1855
 Bien also reported Kingsley using the headgear to
depress and drive ant teeth distally after the
extraction of first promolars.
 Angle in 1889 ,in his text book on orthodontia
discussing occipital anchorage, stated that this
means of anchorage was becoming more
popular for cases of maxillary protrusion.
 Later however, after Angle started using inter
maxillary elastics for the correction of Class II
malocclusions, and he changed his stance on
Extra oral appliance.

In 1898 guilford talked about directional
pull by activating rubber strands of the
“skull cap” above or below the ear
As orthodontics progressed in the early
twentieth century ,however extraoral
appliances and mixed dentition
treatment were abandoned as they
were termed an unnecessary
complication

 Oppenhiem from vienna in 1936 revived
the idea that headgear would serve as a
valuable adjunct to treatment after his
experimental treatment approach to an
actress who rejected visible appliances.
 The result was so rewarding that he
continued this approach and brought it
to the U.S
 He used the headgear to uncrowd teeth
and to correct class II maloclusions,
without having to extract teeth

 In his paper in 1936- oppenhiem says about the
occipital anchorage-’ for the treatment of
similar cases,which form a great portion of our
practice material and which deal with a
forward wandering of the buccal teeth,
especially the canines, and also in the
treatment of class II cases in which we carry
the upper teeth backward rather than the
lower teeth forward, this procedure is in my
opinion most reccomendable.”
Biologic orthodontic therapy and reality. Angle
ortho. 6:157-167. 1936

 Much credit must be given to Kloehn for
reviving the use of extra oral appliances.
 He went on to combine the dental bow
and facebow in a soldered joint.
 He also introduced the elastic neckstrap
to apply traction

High pull headgear also became famous
to
a)Prevent mandibular rotation
b)Attached to upper incisors to keep them
intruded and torqued while retracting
them

Rickets stopped using the high pull headgear in 1950s
claiming they were very slow in class II correction and they
also did not prevent dolichocephalic patterns of facial
growth
Rickets observation with cervical headgear were-
a)there was retraction of maxillary complex measured at
point A
b)There was minimal extrusion of upper 1st molars and incisors
c)The palate rotated in a clockwise direction
The occlusal plane rotated in anticlockwise direction
d)minimal or no adverse rotation of the mandible
Ricketts, the influence of orthodontic treatment on facial
growth and development. 1960

In 1955 graber in his article “extraoral force,
facts and fallacies” quoted
a)There is no evidence that maxillary growth
,per se is affected
b)Bodily distal movement of molars can be
accomplished ,but in most cases it is merely
restrained from coming forward in its normal
path or tipped distally
c)It is possible to impact 2nd molars
temporarily by excessive distal tipping of
first molars

d)Marked improvement in basal relation
can be obtained.
e)Growth is an important factor ,its
presence or absence profoundly
influences the results. Coordination of
treatment with pubertal growth spurt
means a greater likelihood of success.

 Cervical pull
 High pull
 Combination
 Interlandi
 J-hook
 Asymmetric/unilatral
 Reverse pull head gear

Basic element
 Force delivering unit i.e facebow , ‘j-
hooks’
 Force generating unit i.e. Elastic, springs
 Anchor unit i.e. Head cap, neck pad

Face bows: made of stainless steel having a
diameter between 0.040” to 0.050”. It
engages buccal tubes on the first molars.
The methods used to make the inner bow
stop mesial to the 1st molar are:
 Bayonet bends/ horizontal inset bends
which prevent the anterior portion from
impinging on brackets on teeth
 Stops: cylindrical tubes with an internal
diameter corresponding to inner bow
diameter.

Preformed inner loops: serve as adjustable
stops as well as shock absorbers and are
angulated for clearance
The also facilitate necessary unilateral
adjustments to keep the facebow length
as molars gradually move distally and
reduced facebow length as incisors are
retracted

 Acts as a media through which force is
transmitted to the inner arch. Dentaurum
products have a standard bilaterally
symmetrical facebow in which the joint
between the inner and outer bow can
come with or without cuspidhooks and in 3
sizes- short ,medium and long
 Outer bow dimension -0.051’- 0.062’
stainless steel contoured to the check
contour with the inner and outer bow joint
lying between the lips when the inner bow
engages the buccal tube

 The outer bow can be short, medium
or long.
Short – outer bow is lesser in length
than inner bow.
Medium – outer bow length is equal
to inner bow.
Long – outer bow is longer than inner
bow.

 Springs: calibrated tension springs are
available. These have the advantage
that the applied force can be varied.
 Elastics: serve as force elements and are
available in the following forms
 neck bands with strong/medium pull
 extra-oral plastic chains with length 119mm

 Friction release systems these include safety
release to reduce “sling-shot” hazards by
means of clips which release automatically
when pulled with excessive force. they provide
case of assembly and include an inner steel
coil to provide a consistent traction force.
 Prescription tab variable force neckpads: these
provide adjustable calibrated force of 4-18 oz.
 Headcaps: of the following types are available:
preassembled standard universal
preassembeld extra comfort
vertical pull

 Introduced by Kloehn in 1947. it is also known as
the kloehn headgear.
 This was to become the most widely used form of
an extraoral traction appliance to be used in
contempopary orthodontics.

 Since the anchor unit (neck strap) passes
around the patients neck and is
attached to the outerbow to produce a
force acting 5o-10o tangent the occlusal
plane, it is called the cervical pull
headgear .
 Recommended time of wear is 12-
14hrs/day this disto occlusally directed
force has an extrusive effect on the
molars.

 The high-pull facebow is attached to the
maxillary first molars by means of an
outer bow

 The outer bow is bent upwards so that the
point of force application and the direction of
force lies above the centre of resistance of the
maxillary first molars.the inner bow lies passively
in the molar tubes, or it can be expanded if an
increase in transpalatal width is desired
 Rationale justifying the use of a high-pull
headgear-
Cervical pull headgears have certain
drawbacks that are especially undesirable in a
majority of class II division1 cases.
These problems have their origin in the line of
action of the force , generated by a cervical-
pull extraoral traction device , which often
passes below the centre of resistance of the
maxillary first molar.

 As a result of this , it produces
a moment of force which
results, in the mesial tipping of
the roots and a distal crown
inclination of the posterior
maxillary buccal segment.
 An additional drawback of
the cervical pull heargear is
the disto-occlusal orientation
of generated force which
causes extrusion of molars.
this prevents its use in patients
its use in patients having a
high mandibular plane angle.

 The tendency of the cervical-pull
headgear to cause the tipping and
extrusion of molars might compromise
the stability of the orthodontically
corrected dentition.
 So,the concept and utility of high-pull
headgear was put forth, where the
resultant force was directed through the
level of trifuriation of maxillary molars in a
postero-superior direction.

 With the high-pull headgear, it is possible to
change the direction of force in relation to
the centre of resistance of the dental units
to which force is being applied in order to
achieve better control of resulting tooth
movement in a distal direction
 And to modify vertical changes in the
maxillary molar position to correct class II
relationships using a relatively lower
magnitude of forces.

Treatment effects of the high-pull
headgear include
 intrusion and distalization of maxillary
molars
 Anti-clockwise mandibular rotation
 Decreased lower facial height
 Retrusion of incisors

 The interlandi type high pull
headgear
 In this design , the outer bows
are attached to the head
straps of the headgear with
the help of ½’ latex elastics.
 the direction of the applied
force was modified by
changing the point of
attachment of these elastics.

 In order to prevent the distal tipping of
molars, the end of the outer bow must
terminate in the same plane as the centre
of resistance of the upper first molar.
 The inner bow is made parallel to the
occlusal plane and the length of the outer-
bow is reduced so that it does not extent
distal to the maxillary first molar.
 a force of 500gms/side is used with
recommended wear of 12 hrs/day.

 The cervical facebow and the high pull
facebow can be used in combination to
alter the direction of force along the plane
of the occlusion.
 Advocated by arm strong(1971) and
berman(1976)

 The forces produced by extraoral
traction also can be attached anteriorly
by means of j-hooks to the archwire or
the hooks soldered to the archwire.
 Flared maxillary incisors can be retracted
using either a high pull or a straight-pull
headgear combined with j-hooks that
are attached to the arch wire anteriorly
or by using a closing arch supported by
headgear.

 Headgears with j-hooks also are
used to potentiate arch wire
mechanics by helping control
forces incorporated into the
archwire(e.g. torque intrusion)
 J hooks can be applied to the
maxillary teeth in a variety of
force vectors to retract and
intrude the maxillary incisor teeth
 Usually done in edgewise
mechanotherapy

 Armstrong(1971), hickham(1974) and
vaden et al (1986) have used J hooks
with the interlandi headgear to
simultaneously retract maxillary and
mandibular canines

 Asher face bow:
demonstrated by roth
 This is a high pull facebow with
a headcap and a short intra
oral bow
 Used to retract maxillary
incisors in premolar extraction
spaces using 2-6 ounces of
force
 It applies force directly to
maxillary canine brackets.

Advantages:
 Comfortable to wear
 Conserves anchorage
 Simultaneous retraction of both arches.
helps in intrusion of incisors.

 Similar ‘En-masse’ retraction of the
anterior arch was done by Enis Guray et
al (1997)
 They used the interlandi type headgear
with a modified anterior segmental
facebow from canine to canine

 Orthodontic treatment often requires an
extraoral force that will predictably
deliver a greater distal force to one side
of dental arch than to the other.(e.g.
class II molar relationship on one side,
class I on the other)

 The centre of attachment to the inner
bow is moved laterally,thus producing
asymmetrical forces against the two
sides of the dental arches.
 Disadvantage-extended use of this
device will tend to skew the arch to one
side.

 Power arm facebow-one
outer bow is longer/wider
than the other.longer/wider
bow tip is located on side
anticipated to receive
greater distal force.
 Power arm facebow also
generates lateral forces
which tend to move the
favored molar tooth into
lingual crossbite and the
opposite molar into buccal
crossbite.

 Soldered offset facebow-
outer bow is attached to inner
bow by means of a fixed
soldered joint placed on the
side favored to receive greater
distal force.
 Swivel offset facebow-in this
design, outer bow is attached
to inner bow by means of a
swivel joint located in an offset
position in the side favored to
recive greater distal force.
 Said to minimise undesirable
lateral force

 Centre of resistance-
when a force is applied
too a body, the body
resists the force (Newton's
third law of motion). If it is
a free body, this
resistance to movement
can be reduced to one
point called the centre of
resistance. A force
directed through the
centre of resistance will
translate the body.

 Centre of rotation-
The centre of rotation is the point about
which the object rotates. This varies with
the location of the centre of resistance
and the force applied to the object.
Pure rotation occurs when the centre of
rotation is at the centre of resistance.
Pure translation occurs when the centre of
rotation is at an infinite distance away
from the centre of resistance.

a)Maxillary first molar- situated at
trifurcation of the roots
Dermaut LR, Kleutghen JPJ, De Clerck HJJ. Experimental
determination of the center of resistance of the upper first
molar in a macerated, dry human skull submitted to
horizontal headgear traction. Am J Orthod Dentofacial
Orthop 1986;90:29-36.
b)Single rooted tooth- situated at the 33% of
the root length apical to the alveolar crest.
Burstone CJ. The biomechanics of tooth movement. In: Kraus BS,
eds. Vistas in orthodontics. Philadelphia: Lea & Febiger;1962.
p. 197-213.

 Maxillary dental arch- between the roots of 1st and
2nd premolars
 Maxilla/nasomaxillary complex- nanda and goldin
(1980) reported it to be in central part of zygoma.
According to billetet al(2001) it is same as maxillary
arch.
Tanne et al (1995) – at pterygo-maxillary fissure.
 For 4 maxillary incisors- according to matsui et al
(2000) it is located within the mid-sagittal plane,
approximately 6-mm apical and 4-mm posterior to a
line perpendicular to the occlusal plane from the
labial alveolar crest of the central incisor.

 Centre of resistance of the maxilla-
posterior superior aspect of the
zygomaticomaxilary suture – stockli and
tussherre

 Greenspan in his study in 1970 , gave
reference charts for clinical use,
simplifying the direction of pull of the
head gear in accordance with different
lengths of the outer bow, and its actions.
 His analogy of the tooth movement was
that of a flywheel which revolved around
a fixed axis,and was affected by different
directions of force.

 When the outer bow lies along the lfo, no
moment occurs ,and the force system
will be reduced to a bodlily movement in
a posterior and extrusive direction.outer
bow is equal length to inner bow.
 If the outer bow is placed above this
line,it passes distal to centre of
resistance.the moment produced by the
force will be in countreclockwise
direction.outer bow is long.

 If the outer bow is adjusted below this line
the moment created will be
clockwise.however the direction of the
forces are the same-extrusive and
posterior.it tends to steepen occlusal plane
in such cases.
 If the outer-bow is located below the
neckstrap, the resultant force will be small
intrusive one, instead of extrusive. ofcourse
a distal force and large clockwise moment
will also be produced.

 The directional pull provided by the cervical
headgear is especially advantageous in
treating short-face class II maxillary
protrusive cases with low mandibular plane
angles and deep bites, where it is desirable
to extrude the upper posterior teeth
 Also the clockwise moment that is so readily
produced with this headgear is very
effective in helping conserve anchorage in
extraction cases.

 This style headgear always produces an
intrusive and posterior direction of pull
due to the position of the headcap.
 The direction of the moment that is
produced is dependent on the position
of the outerbow

 If the outerbow is placed anterior ,either
above or below the occlusal plane level,
the moment produced will be
counterclockwise.
 On the other hand, if the outer bow is
placed posterior to this line, the moment
produced will be in clockwise direction.
 The magnitude of this moment will be
proportional to the distance of the outer
bow to CR.

 If a distal and intrusive movement with
no moment is desired, the outer bow
must be placed somewhere along
centre of resistance.
 This force system would be beneficial in
a long-face class II patient with high
mandibular plane angle, where intrusion
of maxillary molars would decrease
facial height and improve the facial
profile.

 This style headgear is a combination of
highpull and cervical headgear, with the
advantage of increased versatility.
depending on the force system desired, the
orthodontist has the opportunity to change
the location of the line of force.
 The prime advantage of this headgear is its
ability to produce an essentially pure
posterior translatory force.
 This is accomplished by placing the Line of
force through the centre of resistance,
parallel to the occlusal plane. clinically, this
means bending the outer bow to the same
level as CR, and hooking the elastic to a
notch at the same vertical level.

 The relation of the outer bow to the Line
of force dictates the direction and
magnitude of forces and moments.
 Placing the outerbow above the Line of
force will produce a posterior
force,counter clockwise rotation, and
most often intrusive force.

 If the outer bow is below the Line of force,
the force produced will be posterior and
superior, and the moment will be in a
clockwise direction.
 The straight pull headgear is the appliance
of choice in a class II malocclusion with no
vertical problems. it is also the headgear of
preference when the main thrust of
headgear wear is to prevent anterior
migration of maxillary teeth,or possibly even
translate them posteriorly .

 The main purpose of this headgear is to
produce an intrusive direction of force to
maxillary teeth, with posteriorly directed
forces.if the outer bow is hooked to the
headcap so that the line of force is
perpendicular to the occlusal plane and
through the CR, pure intrusion may take place.
 The vertical-pull headgear is not commonly
used as are the others.however, it is very useful
when pure intrusion of buccal segments is
required, as in the class I open-bite patient.

 Extra oral traction has been shown to
produce a variety of skeletal and dento
alveolar effects in class II patients.
 Even though there is some agreement
among investigators as to the effects
produced, the clinical management of
the appliance, the direction of force
applied and the amount of force used
may explain some of the differences
among investigation.

 Maxillary skeletal position
A primary treatment effect of extraoral traction is
the restriction of maxillary skeletal growth.there
is virtually a universal agreement that because
of treatment, point A is repositioned posteriorly
relative to the remainder of the face, resulting
in a reduction in maxillary prognathism.
Wieslander(1974) has shown that this technique
also influences the cranial base by producing
a counterclockwise tilting of the spheno-
ethmoid plane during 3-4 years of treatment
with a headgear.

 Distal movement of the maxillary molars is a
typical effect produced by cervical headgear
therapy. in contrast, Hubbard and co-workers
(1994), who studied a sample of patients
treated by kloehn, reported a mesial
movement of the first molar.
 Extrusion of the maxillary molars also has been
observed, with two to three times as much
extrusion reported as would be expected
during normal growth.on the other hand,
Hubbard and colleagues did not observe
molar extrusion.

 There is virtually no literature that
addresses the effect of the cervical-pull
facebow on the mandbular dentition
other than the treatment effects that are
produced in association with fixed
appliance treatment. there appears to
be no effect

 The antero-posterior relationship of the chin has
been correlated to the amount of vertical
opening produced during treatment. A
downward and backward rotation of the
mandible and a similar movement of point B
and pogonion have been reported, as has an
opening of the mandibular plane angle.
 Kloehn(1947) ,ringenberg and butts(1970)
report no change in the SNB angle,but other
investigators (mcnamara, 1996, Graber 1956)
note a posterior movement of point B.

 There is no universal agreement as to the
effect of cervical headgear treatment
on the vertical dimension, as
investigators have differed in describing
the effect of this type of therapy on the
various aspects of vertical facial
measures.

 An increase in the mandibular plane
angle as the mandible is hinged open
has been reported by many investigators
 An opening of the bite and an increase
in lower anterior facial height also has
been a frequent finding. Klien(1956)
report that extraoral force tends to open
the Y axis angle and lengthen the face
more than would occur with normal
growth.

 A high pull headgear has been
recommended to reduce the extrusion
of the maxillary first molars.
 In contrast, ringenberg and butts (1970),
baumrind (1978) , and hubbard and
coworkers (1994) report a closure of the
mandibular plane angle with treatment,
where as others reported no change.

 Investigators have differed as to the effect of
extraoral traction on the orientation of the
occlusal plane relative to the cranial base
 The anatomic occlusal plane normally closes
with age. Klien(1957), King(1957) and Hubbard
et al (1994) reported that the angle of the
occlusal plane remain unchanged relative to
the cranial base.
 Hubbard et al noted that the functional
occlusal plane closed slightly with treatment.
he stated it became more or less parallel to the
s-n plane

 The palatal plane has been shown to tip
anteriorly with an uneven descent,
resulting in the anterior nasal spine
tipping more inferiorly than the posterior
nasal spine.
 On the other hand, Kloehn(1961) and
Boecler and co-workers (1989) noted no
change in the palatal plane.

 In the literature, changes in the transverse
dimension with extra oral traction has been
minimal
 Ghafari et al (1994) ,who conducted a
comparative study of the straight- pull
headgear and FR-2 appliance of
frankel,The inner bow of the facebow was
adjusted at every appointment ”to avoid
any constriction or major expansion of the
intermolar distance”resulting in a total
expansion of the inner bow of 1.5-2.0mm.

 Ghafari et al noted increases not only in
intermolar distance, but in inter canine
distance as well

 Stienberg, Burstone, Anderson( angle
orthod 2004) did a study to see whether
high pull headgear can prevent
steepening/ extrusion of buccal segments
during incisor retrusion and whether it can
increase the rate of incisor intrusion.
 Results showed that high pull headgear has
no effect on extrusion of buccal segments
during incisor retrusion nor any effect on
rate of intrusion.

 Haulabakis et al (ajo 2004) studied the
effect of cervical headgear on patient
with high or low mandibular plane angle
and assessed the “myth” of posterior
mandibular rotation.
 They concluded that regardless of
treatment taken, vertical skeletal
relationship was not affected.

 Leandro et al (AJO 2005) studied the
effects of cervical headgear on space
available for maxillary 2ndmolar to erupt.
 They suggested that despite restriction of
movement of maxillary 1st molar and
maxilla there was sufficient space for 2nd
molar to erupt because of posterior
displacement of PTM point and growth
at maxillary tuberosity.

 Hubbard et al(angle 1994) studied the
effects of orthodontic treatment with the
use of cervical headgear in class II
malocclusion patients.
 Overall the results showed changes were
very close to what would occur as a result
of normal growth in class I individuals
 Maxillary 1st molars continue to grow
forward, cranial base showed very little
change.
 Mandibular plane angle did not increase
appreciably with treatment

 Brite melsen (AJO 1978) have reported
that influence of headgear on growth
pattern of facial skeleton was reversible.

 Pfeiffer attached the HG directly to the
activator and applied occipital traction
to achieve better vertical and rotational
control during class II treatment.
 Bass modified the appliance and used a
J hook headgear.

 The primary treatment objective is to
restrict the developmental contributions
that tend to cause a skeletal class II and
at the same time attempt to correct
antero posterior relation of jaws.
 Usage mainly limited to mixed dentition
with force application of 250 grms/side.

 First decribed by Wieslander (1984) Wherein
the headgear is fixed to a tube soldered to
the molar attachment.
 High pullforce direction using 100 gms/side
of force and worn for 12-18 hrs/day in mixed
dentiton period.
 Produces a synergestic effect on correction
of skeletal class II cases wherein the herbst
appliance stimulates mandibular growth
while this headgear force redirects maxillary
growth.

 There are three main uses of headgear
force
1. Anchorage control
2. Tooth movement
3. Orthopedic changes

 In class II treatment, headgear force can
play a major role in ensuring that buccal
segment teeth do not move mesially
when anteriors are retracted.
 Intraoral mechanics often result in
eruption of teeth.
 Headgear produces a vertical force
greater than the force of side effect
 Inner and outer bows can be of any
shape, convolution, and length.

 Adjustment of outer bow such that a
horizontal force is produced that passes
through the center of resistance of maxillary
first molar and the patient wears the
headgear at a level of 14 hours each night
consistently, clinical experience shows that
the first molars will move distally 2mm in 24
months without tipping.
 Distal tipping is not preferred as finite
element studies have shown that the stress
levels at the periodontal ligament-bone and
tooth interfaces are beyond acceptable
limits even when tipping forces are very light.

Intrusion in deep bite cases
 Headgear can be used in adjunct to upper utility arch.
High pull headgear allows more intrusive control
permitting maximal incisor movement whilst minimizing
possible molar tipping and also used to deliver
orthopedic force on developed premaxillary segment.
 120 to 150 g force is delivered.
Distalization of molars
 Headgear is the obvious choice. Fill time wear is
necessary. Molar extrusion should be avoided so
straight pull or high pull is used and not cervical.
 Force – 300g on each side.
 Unilateral molar distalization in unilateral class II can be
achieved by asymmetric cervical headgear

 If the headgear is applied
through the center of
resistance of maxilla, which is
in the posterosuperior part of
zygomaticomaxillary suture

 If a preadolescent patient wears the headgear at
least 12 hours each night , the forward component
of maxillary growth is redirected.
 Cervical traction produces stresses along the
frontal process of maxilla, zygomaticofrontal suture,
and the junction of the palatine bones, areas
where high-pull traction produced no observable
effect. Only the high-pull headgear produces stress
at the anterior junction of maxillae (anterior nasal
spine).

Pterygoid plates of the sphenoid
 High stress develops upon activation.
 These stresses begin in the middle of the
posterior curvature of the plates and just
superior to their anterior junction with the
palatine bone and maxilla.
 As the force increases, the stresses progress
superiorly toward the body of the sphenoid
bone.
Zygomatic arches
 Cervical and high pull both produce similar
stress .
 Starts at the inferior border of the
zygomaticotemporal suture and proceeds
posteriorly along the zygomatic process of
temporal bone.
 Cervical force produces more intensity at lower
load level.

Junction of the maxilla with the lacrimal and
ethmoid bones
 Both cervical and high pull produce a stress
concentration at the junction of the maxilla
with the lacrimal bones and with the orbital
plates of ethmoid.
Maxillary teeth
 High stresses around maxillary molars with
cervical traction. These located around the
middle third of the mesiobuccal root and
around distobuccal root at a position toward
apex.
 Also distal to second molar.
Frontal process of maxilla
 Stresses produced anterior to nasolacrimal
foramen only with cervical pull.

Palate
 Cervical traction produces stress in posterior region
developing in the horizontal portion of palatine
bones. High pull has no effect.
Anterior junction of left and right maxillae
 Only high pull produces forces below the anterior
nasal spine and just lateral to the suture between
the two maxillae.

Sphenomaxillary suture- large compressive stresses.
Temporozygomatic suture- tensile normal stresses
Sphenozygomatic suture- large tensile stresses
Frontozygomatic suture- large compressive stress
Frontomaxillary suture- large tensile stress
 Sphenomaxillary and sphenozygomatic sutures, in
particular, resisted the posterior displacement of
the complex
 Stresses in the nasomaxillary sutures are varied by
the direction of headgear force, and the force
applied in the direction closest to that of the CRe
may produce the most effective sutural
modification for controlling maxillary growth.

 The appliance should be simple and
mechanically sound enough to be used as a
therapeutic procedure for treatment of
prognathic syndromes, maxillary retrutions, clefts
& mandibular prognathism.
 HICKHAM (1972) claims he was the first to use a
reverse headgear. However this modality was
made popular by DELAIRE around the same
time.
 Delaire, Verdon, and Floor have extensively used
a facial mask to protract the maxilla anteriorly.
Elastics generating forces of 1,000 to 2,000 Gm.
are used from distal of the maxillary molars to the
wires of the mask to move the maxilla anteriorly.

 Armstrong applied 500 Gm. of force via chin cups
on 100 adolescent patients with mandibular
prognathism. He reported that half of his patients
showed improvement in the Class III profile,
whereas none of the control, nontreated patients
showed any favorable change.
 Graber and Chung reported results in patients
treated with chin cups for 12 to 14 hours each day
with a force of 1.5 to 2 pounds on each side. They
showed that mandibular growth could be
redirected with a chin cup. They asserted that
continuous use of the appliance for a long period
or through active growth was necessary to achieve
stable results.

 Nelson described an appliance which used anterior pull on
the maxilla by means of a football-type helmet. Haas showed
downward and forward movement of the maxilla as a result
of palatal expansion. The maxillary effect was enhanced by
the use of Class III elastics from a chin cup to the distal aspect
of the palatal appliance.
 Several clinical studies in the past have noted that treatment
of patients in skeletal Class III should include protraction of the
maxilla with or without chin cups. Graber noted that
restriction of growth or distal movement of the mandible was
impossible.

1. Growing patients having a prognathic mandible
and a retrusive maxilla ( class III malocclusion)
2. For selective rearrangement of the palatal shelves
in cleft patients.

 Anchorage from chin: force is transmitted to
the condylar cartilage & thus alters the
growth of mandible.
 Anchorage from skull : disadvantage include
patient discomfort while sleeping, cost, and
time required in fabrication and fixing.
 Anchorage from chin & forehead : no
excessive force is exerted onto the growth
cartilage. Disadvantage is difficulty in speech
& compromise in aesthetics & comfort.

1. Amount of force- the amount of force
required to bring about skeletal changes
is about 1 pound or 450 gms per side.
2. Direction of force- 15 – 20 degree
downward pull to the occlusal plane to
produce a pure forward translatory
motion of the maxilla. If the line of force
is parallel to the occlusal plane, a
forward translation as well as an upward
rotation takes place.

3. Duration of force- time taken to achieve
desired results is proportional to the
amount of force utilized. Low forces (250
gm/ side) take 13 months to produce
desired results. High forces ( 1600- 3000
gms) reduced treatment time to 4 – 21
days.
4. Frequency of use- 12 to 14 hours of wear
a day

Parts of a reverse pull headgear
1.Chin cup : is used to take anchorage from the chin area. It can
be ready made or can be fabricated from an impression of
the patients gonial region. It is
connected to the rest of the face mask assembly by means of
metal rods.
2. Forehead cap : use to derive anchorage from the forehead.
3. Elastics : used to apply a forward traction on the upper arch.
Vertical posts of the chin cup are used to attach the elastics
onto the molar tubes or hook soldered on the arch wire. It is
purely for tooth movement.
4. Intraoral appliance : traction hooks are placed either in the
molar or premolar region.
5. 5. Metal frame : It connects the various components such as
the chin cup and forehead cap. It also has provision to
receive elastics from intraoral appliance.

 Also called as “protraction headgear”
 When an anterior protractory force is required, a protraction
headgear is used.
 Principle – pulling force on the maxillary structures with reciprocal
pushing force on the forehead or mandible through facial
anchorage.
 A reverse pull headgear basically consists of a rigid framework,
which takes anchorage from chin or forehead or both for anterior
traction of maxilla using extra oral elastics that generate large
amounts of force up to 1 kg or more.

1. Protraction headgear by Hickham :
 Uses the chin and top of the head for anchorage.
 Force distribution is – 15% head, 85% chin.
 Consists of 2 short arms in front of the mouth to engage
maxillary protraction elastics.
 2 long arms run parallel to the lower border of the
mandible & go vertically up from the angle of the
mandible and end behind the ears.
 An elastic strap is attached to the end of the long arms
to encircle the head.
 Advantages –
1) better aesthetics
2) comfort
3) option of unilateral force applicability.

2. Face mask of Delaire:
 Uses the chin and forehead for
support.
 Appliance is made up of a rigid
wire framework, which is squarish
& kept away from the face.
 It has a forehead cap and a chin
cup with a wire running in front of
the mouth used for elastic
attachment.

Tubinger model :
 Modified type of Delaire face mask.
 Consists of a chin cup from which
originates 2 rods that run in the
midline & is shaped to avoid the
interference of nose.
 The superior ends of the 2 rods house
a forehead cap from which elastics
encircle the head.

4)Petit type of face mask :
 Modified Delaire face mask.
 Consists of a chin cup & a forehead
cap with a single rod running in the
midline from forehead cap to chin
cup.
 A crossbar at the level of the mouth is used to
engage elastics.
 Advantage – forehead cap, chin cup & the
cross bar can be adjusted to suit the patient.
An Orthopedic Approach to the Treatment of Class III
Malocclusion in Young Patients
VOLUME 21 : NUMBER 09 : PAGES (598-608) 1987
JAMES A. MCNAMARA, JR., DDS, PHD

Evidences
 Baccetti et al (1998) Significant skeletal effects of early
treatment of Class III malocclusions with maxillary
expansion and face-mask therapy
 Kim et al (1999). A meta-analysis of the effectiveness of
protraction facemask therapy. Patients who did not
have palatal expansion had longer treatment times
and ended up with more upper incisor proclination -
i.e.: more dental change and less skeletal change.
 Franchi et al (2004) concluded that it was possible to
achieve a 2 mm advancement of the maxilla that
would withstand the active growth period if RME and
protraction head gear was undertaken in the
deciduous dentition or early mixed dentition

1. fabricate and bond/cement the rapid maxillary expansion appliance
2. Appliance is activated once per day until the desired increase in maxillary
width has been obtained.
3. If patients do not need an increase in maxillary width, the appliance is still
activated for 7-10 days to disrupt the maxillary sutural system (Haas, 1965)
4. then protraction headgear is fitted.
5. A heavy orthopaedic force of 400g per side is applied to the maxillary
complex
6. Force vector should be 15-30 degree below the horizontal
7. The patient wears the facial mask for at least 12-14 hours per day
8. Active treatment should be limited to 9-12 months because of the risk of
decalcification of the dentition
9. Retention with a number of appliances: acrylic maxillary retainer, FR-3
appliance or a chin cup (seldom used).
10. Patient should be warned of the possibility of orthognathic treatment if
growth is unfavorable
11. Labial root torque: Most class 3 patients demonstrate considerable proclination of
the upper labial segment at the end of treatment.. Catania et al (1990)
recommend in his case report to use inverted U incisor bracket to counteract the
effect of proclination.

 In 2005 Eric Liou et al introduced the
concept of ALT-RAMEC alternate rapid
maxillary expansion and contraction
 They stated that 5 weeks of ALT RAMEC
opened the circumaxillary sutures more
than RME
Liou, E. J. and W. C. Tsai . A new protocol for maxillary
protraction in cleft patients: repetitive weekly protocol of
alternate rapid maxillary expansions and constrictions. Cleft
Palate Craniofac J 2005. 42:121–127

 Forward movement of maxilla and point A
 Reduction in mandibular projection,
satisfactory maxilla-mandibular relationship
 According to Mcdonald et al, Bacetti et al,
Sinclaire et al – there was a
counterclockwise rotation of the maxilla
 Reverse overjet in anteriors was seen
 Improvement in molar relationship
 Downward and backward rotation of the
mandible

 Also referred to as chin cap.
 It is an extra oral orthopedic device
that covers the chin and is connected
to a head gear.
 Used to restrict the forward and
downward growth of the mandible.

1) Occipital pull chin cup –
 Derives anchorage from the occipital and parietal
region.
 Used in class III malocclusions associated with mild
to moderate mandibular prognathism.
 Also indicated in patients with
slightly protrusive lower incisors
as they invariably produce
lingual tipping of the lower
incisors.

2) Vertical pull chin cup –
 Indicated in patients with steep
mandibular plane angle and
excessive anterior facial height.
 These patients usually exhibit
an anterior open bite.

 Chin cups are fabricated individually for
the patient or pre- fabricated
commercially available chin cups are
used.
 The fabrication of chin cup requires an
impression to be taken of the chin area.
 The cast is poured and the chin cup is
fabricated using self cure acrylic resins.

 At the time of appliance delivery a force
of 150-300 grams per side is used.
 Over the next 2 months the force is
gradually increased to 450-700 grams
per side.
 The patient is asked to wear the
appliance for 12-14 hours a day to
achieve the desired results

1) Patients with mild skeletal
prognathism of the mandible.
2) In case of increased facial height.
3) Patients who has well aligned or
protrusive, but not retroclined
mandibular incisors.

 To obtain desired dento-skeletal effect with
extra oral traction, type of appliance,
amount of force, location of centers of
resistance of teeth, maxilla & craniofacial
type must be considered.
 Different subjects may respond differently to
same type of extra oral traction
 Cervical, combination and occipital
facebow have similar A-P and vertical
effects in growing patients.

 Birte melsen and michel dalsta: distal molar
movement , AJODO 2003; 123:374-8
 Leandro M .Piva, Helisio R.Leite, Maria
O’Reilly: effects of cervical headgear and
fixed appliances on space available for
maxillary 2nd molar. AJODO 2005,
128(#),366-371
 Haulabakis NB ,Sifakakis IB: the effect of
cervical headgear on patient with high or
low mandibular plane angle and the myth
of posterior mandibular rotation

 Serdar usumex, metin orhan: effect of
cervical headgear wear on dynamic
measurments of head position. EJO
2005(27);437-442
 R.H.A.Samuels, N breziniak: orthodontic
facebows: safety issues and current
management. J.O.2002(29); 101-107
 Keith Godfrey: extra oral retraction
mechanics: a review. Aust.ortho j 2004,
20:31-40

 Kloehn SJ :Orthodontics- force or persuaion
angle ortho 1953, 23:56-65
 Arm strong MM :controlling the magnitude ,
duration and direction of extra oral force.
AJO, 1971, 59:217-243
 Jacobson A: A key tounderstaing of
extraoral forces. AJO 1979,75:361-386.
 Weislander L: Long term effects of
treatment with headgear-herbst appliance
in early mixed dentition. AJO 1993, 104: 319-
329

 Hershey HG, Houghton CW , Burstone
CJ:Unilateral facebows; a theoretical
and laboratory analysis. AJO
1981;79;229-249
 Nanda R: Biomechanics in clicnial
orthodontics. 1st edition, philadelphia,
WB Saunders, 1997:130- 145
 Turner PJ: Extra oral traction. Dent
update, 1991:18:197-203

 Firouz.M, Zernik J , Nanda R: denta; and
orthopedic effects of high pull headgear
in treatment of class II div I malocclusion.
AJO, 1992;102:197-205
 Graber TM :Extra oral force- facts and
fallacies. AJO 1955,41:490-505

 An important aspect of using extra oral
traction is whether appliance is being
worn as instructed.
 Patients compliance can be improved if
both parents and clinician provide
motivation.

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