Headgear

CONTENTS
• Introduction
• Evolution Of Headgear
• Classification Of Headgear
• Biomechanics Of Headgear Use
• Clinical Uses
• Effects Of HeadgearTreatment
• Clinical Steps

• Types Of Headgear
• ComparisonWith Other Functional Appliances
• CombinationTherapy
• Reverse Pull Headgear
• Safety Issues
• LongTerm Effects
• Conclusion
• References

INTRODUCTION
• Headgears are the most common among all the orthopedic
appliances.
• This family of appliance is typically used to restrict the
downward and forward growth of the maxilla.
• Maxillary growth is restrained and/or redirected so that basal
bones become more harmoniously related to one another as
the unimpeded mandible “catches up” during normal growth.

EVOLUTION OF THE APPLIANCE
• “One surprising feature of the history is the frequency
of the rediscovery of identical principles, their
materialization differing only in minutiae of
manufacture”
Dr. Angle(1900)

EVOLUTION OF HEADGEAR
The use of extra-oral force is around 100 years old.
The “headcap” was described by
Kingsley in 1866 and Farrar in 1870’s. It’s
objective was limited to retraction of
upper teeth.
Angle in 1888 described his extra-
oral attachment for maxillary dental
protrusion .It had a long pin soldered
onto E arch at the midline

Kingsley’s Headgear Angle’s Headgear

In 1898, Guilford talked about directional pull by activating
rubber bands of skullcap above or below the ear.
In 1888, Goddard described the making of a vulcanite
casing for moulding black rubber against anterior teeth to
which was attached headcap with rubber elastic bands.

In 1921, CalvinCase extended the application of extraoral therapy.
Here was the first solid mention to the upper molars being moved
distally-the labial bar was extended to the bicuspid area on the
dental archwire and forced the molars and entire arch backward.

In 1936, Oppenhiem inVienna was called upon to treat an
actress who rejected visible appliances. He placed molar bands
and dental bow all the way to the molars and applied the
headcap.
Silas Kloehn , Buleah Nelson andWilliam B Downs achieved
success with this technique.
Kloehn went on to combine the dental bow and the facebow in
a soldered joint making the center apparatus removable.

In 1938, first cephalometric presentation of treated cases
by Brodie. It was determined that the treatment used at
this time had little effect on structures other than alveolus
and successes could be usually explained by a holding of
the maxillary dentition while growth of the mandible
occurred.
In 1946, Epstein presented his master thesis on extraoral
traction. He found positive distal molar movement. No
maxillary alteration was noted.

Ricketts and Downs used only neck strap portion
of Kloehn headcap. Kloehn in the meantime
also used only the neckstrap.

In 1950, Fisher attached smaller dental bow to the edgewise archwire
In 1951, Jarabak introduced extraoral traction by attaching hooks on
the archwires with anteriors banded with neckstrap or straight pull.
In 1960, McCulloch reintroduced highpull to intrude upper incisors.
In 1953, Buleah Nelson had shown posterior shift of pt A by 5mm.

Brass wire was wrapped dental and face bow to contact andact as
soldering assembly.The ends remained flexible and the force at the
apex of the arch moved the molars sideways and contributed to arch
expansion. Beads of solder employed as stops against the molar tubes.
To prevent distal tipping, outer bow was extended upward till tragus
and this helped in molar extrusion which inturn aided in bite opening
and tubes shifted gingivally.
By 1955, FACEBOWS WERE MADE COMMERCIALLY.Two errors were
introduced
Dental bow made too rigid
Dental arch was bent on a radius too small for a normal dental arch

In 1954, Ricketts introduced expansion and contraction
type headgears.
Effects of cervical headgear noted.-suture widening-
opening of nasal suture-palate tipping downward-took
soft tissue nose with it.
Schudy recognised undesirable mandibular rotation and
anti-Kloehn move took place. Neck strap was replaced by
oblique pull.Proved by RM computer data analysis.

In 1963,Weislander treated patients with Kloehn type headgear,
which utilized a neck strap and 300-400gm of force. Showed
skeletal changes with reorientation of jaw relationships.
Jacobson in 1976 explained the mechanics associated with
headgear therapy.
In 1978Teuscher used headgear with activators. And
subsequently in 1980's and 1990's many people employed
headgear with their appliances like with Clark’s twin block.

AccordingTo use
-To distalize
maxillary dentition-
Face bow headgear
-To protract
maxillary dentition-
Face mask/ Reverse
Pull headgear

Reverse Pull HeadgearFacebow Headgear

AccordingTo Root
(1975) suggested
simplified classification
Attached to
teeth
Attached to
arch wire - J-
Hook headgear

Acc0rding to pull
High pull
Occipital/parietal
Straight pull
Low pull
Cervical/kloehn

High-pull Headgear Straight-pull Headgear Cervical -pull Headgear

Based on where
soldered joint b/w
outer & inner bow
placed-
Asymmetric
headgear-
Fixed type Swivel type
Symmetric-
headgear

Parts Of Face-bow Headgear
• Face bow
• Force element
• Head cap or cervical strap

FACE BOW
• Metallic component that transmits extra oral forces on
posterior teeth.
• Consists of-
– Outer bow
– Inner bow
– Junction

Face bows are of two types-
Inner and outer bow type
J-hook type- Each J-hook consists of a 0.072" wire
contoured so as to fit over a small soldered stop on the arch
wire, usually mesial to upper lateral incisor.

• Outer bow-
Made of 0.072” stiff round wire contoured to fit face.
Can be
– Short
– Medium
– Long
Distal end curved to form hook- gives attachment to
force element.

The outer bow ends anteriorly to the ears. In all cases, the outer bow
is positioned in the horizontal plane parallel to and even with the
inner bow.
When using a high pull retractor, the end of the outer bow should
coincide with the location of the maxillary first molars. It is bent 60
degree angle superior to horizontal.The outer bow must be adjusted
fit the face of the patient. Should be 5 to 10mm away from cheeks.

Outer bow resting passively
between lips
Outer bow several
millimeters from cheek

Length of outer bow is critical to the desired
effect

• Inner bow-
– Made of 0.045” or 0.051” round
stainless steel wire contoured
around dental arch & molars.
– Inserted into max. 1st molar buccal
tubes
– Stops placed mesial to molar tubes
on it to prevent it sliding too far
through tubes.

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.
U’ loop : have the advantage that it will allow for the adjustment to
the antero-posterior length of the inner arch during treatment. This
is necessary when the upper molars are being moved distally , in
order to clear the bow from incisors

Trevor Johnson friction stops: with internal diameter of 0.045"
which can be soldered to inner bow to serve as stops.
Preformed inner loops: serve as adjustable stops as well as shock
absorbers and are angulated for clearance.They also facilitate
necessary unilateral adjustments to keep the facebow comfortably
centered, increase facebow length as molars gradually move
distally & reduce facebow length as incisors are retracted.

Proper adjustment of the inner bow will allow the wire to slide in
and out of the headgear tubes easily when the posterior strap is
not attached.
Adjustments to the inner bow can be made in six directions:
bucco-lingually, superior- inferiorly, anteroposteriorly.
First Bucco-lingual force is controlled. If the bow is inserted into
one headgear tube, the other bow end should be expanded
approximately 5mm buccal to the opposite tube.
This expansion bend is made near the anterior portion of the inner
bow

As a class II molar relationship is corrected, the relative forward
movement of the lower arch will produce a cross bite tendency
unless the upper arch width is expanded
If maxillary arch expansion is desired and a face bow is used, a greater
amount of expansive force must be built into the inner bow. Inner
bow is expanded.

Vertical adjustments can be made at molar adjustment loops

When the patient closes his mouth and relaxes his lips, the anterior
junction of the inner and outer bows should not be pushing either lip
in vertical direction.
The bow should be in a passive position between the lips. In order to
maintain this position , the posterior ends of the inner bow are
adjusted superiorly or inferiorly.
Antero-posterior adjustment. Inner-outer bow junction is just
anterior to the point where the lips seal. It may be necessary to
enlarge or constrict the loops in the inner bow to achieve this
position

• Junction –
– Rigid joint b/w inner & outer bow.
– Can be soldered, wire wrapped
soldered or welded joint.
– Placed in-
• Midline- Symmetric Headgear
• Off Centered– Asymmetric
Headgear

Force element
• Provides force to bring about
desired effect.
• Comprise of springs, elastics &
other stretchable materials.
• Connects face bow to head cap
or neck strap.

Springs : Calibrated tension springs are available. They 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
• Extraoral plastic chins.
Safety pads : for elastic bands Neck pads with length 180 mm Flexi
pads in roll form for individual size.

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.

Head cap or cervical strap
• Takes anchorage from rigid
skull bones or back of neck.
• Selection based on pt.
needs.

CLASS II CORRECTION
There are 2 primary treatment goals for the stable
correction of class II malocclusion:
•The first is to flatten the occlusal plane during treatment.
•The second goal is to hinge the mandible closed during
treatment.
Both goals contribute to overtreatment of class II
relationships and therefore contribute to the stability of the
final treatment result.

• Force - changes or tends to change the position of
rest of body or its uniform motion in straight line.
• Centre of resistance- point where resultant of
constraining forces when acting will tend to cause
pure translation of body in direction of force.
– Fixed point.
Mechanical principles that need to be
defined include the following-

According toWorms et al (1973) – CR of max. 1st molar
at trifurcation of roots
Poulton (1959)- geometric centre of fully banded max.
arch- b/w premolar roots- designated as “M”

– Barton (1972)- CR of banded max. arch will vary
according to number of teeth banded & size of their
roots.

Braun et al, 1999
• Holding amalgam plugger in the maxillary vestibular
region while the teeth are in occlusion and soft tissues and
lips are relaxed.Then facing buccally amalgam plugger is
positioned at one half of the distance from inferior border
of the orbit to the functional occlusal plane and
corresponding to the distal contact of maxillary first molar.
• A mark is made on the skin and checked for asymmetry.

• Centre of rotation- point around which body will rotate
or tip.
– Changes acc. to external force application
– If line of action of force (LOF) is above CR- centre of
rotation moves coronally & one gets
counterclockwise moment.
– Vice versa if LOF passes below CR

• Line of action – direction in which force acts. Line
connecting point of origin to point of attachment.
• Point of origin of force – anchorage from occipital or
cervical region.

• Point of attachment of force – refers to hook present on
distal end of outer bow to which force element is attached.
– Direction of force can be altered by altering point of
attachment
Varying length varying angle b/w
of outer bow outer & inner bow

Zero moment Line of force (LFO): is a line that connects the center of
resistance of the molar to the point of force application on the
cervical strap or the headgear strap
The different moments and forces produced by the different
headgear depend on the situation of the outer bow in relation to the
LFO.
Contasti GI , Legan HL.Biomechanical guidelines for headgear application. J Clin Orthod
1982;16(5):308-12

• Contasti GI , Legan HL.Biomechanical guidelines for headgear
application. J Clin Orthod 1982;16(5):308-12

Cervical Pull Headgear
The decision to treat with cervical headgear needs to be based on a
complete understanding of the desired tooth movement and the force
system that is produced with this headgear style.
The different moments and forces produced by the cervical headgear
depend on the situation of the outer bow in relation to the LFO.

When the outer bow ends anywhere on this line, the displacement
of molar will always be translational. Outer bow is equal length to
inner bow.
The amount of force would vary depending on how far away the
end of outer bow is from the point of application, or how much
elastic stretches.

If the outer bow is placed above this line, it passes distal to
center of resistance the moment produced by the force will
be in a counterclockwise 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.Tends to steepen
occlusal plane. In such cases outer bow is short length..

If the outer bow is located below the neckstrap, the resultant force
will be a small intrusive one, instead of extrusive. Of course, a distal
force and large clockwise moment will also be produced
The direction of 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.

High Pull Headgear
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
outer bow .
If the outer bow is placed anterior to the LFO, 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 a clockwise direction.

The magnitude of this moment will be proportional to the distance
of the outer bow to the CR.
If a distal and intrusive movement with no moment is desired, the
outer bow must be placed somewhere along the LFO.

This force system would be beneficial in a long-face Class II patient
with a high mandibular plane angle, where intrusion of maxillary
molars would decrease facial height and improve the facial profile.

Straight Pull Headgear
This style headgear is a combination of the high-pull 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 LFO.
The prime advantage of this headgear is its ability to produce an
essentially pure posterior translatory force.

This is accomplished by placing the LFO through the center 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 LFO dictates the direction and
magnitude of forces and moments. Placing the outer bow above the
LFO will produce a posterior force, counterclockwise rotation, and
most often an intrusive force

If the outer bow is below the LFO, the force produced will be posterior
and superior, and the moment will be in a clockwise direction.

The straight-pull is the headgear 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.

Vertical Pull Headgear
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 as 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.

The head is divided into two components: the anterior component
from the LFO forward and the posterior component located behind the
LFO.
If the outer bow is placed anywhere in the anterior compartment, the
moment created will be counterclockwise, and the forces produced
will be intrusive and posterior.
If the outer bow is placed anywhere in the posterior section, the
moment will be clockwise and the vertical force will be intrusive, but
the horizontal force will be forward

Asymmetric Headgear
Right versus left asymmetries can be corrected using transpalatal or
lingual arches to correct asymmetric molar axial inclinations. The same
mechanism can be used to correct asymmetric molar rotations. If buccal
occlusion is asymmetric e.g. Class I on one side and class II on the other
side, without asymmetries either in molar axial inclinations or in
rotations, then it is most logical to achieve the correction with
asymmetric headgear.
Distal forces exist on both sides, but they are three times greater on the
long outer bow side than on the short outer bow side

ASYMMETRIC HEADGEAR
• Asymmetric headgear is used when different distalization forces
are needed on one side of the jaw than the other to correct a Class
II molar relationship. It is effective in producing asymmetric
distalization of molars; simultaneously undesirable lateral
displacing forces are found which may lead to posterior crossbite.
• Lateral displacement is directly proportional to the asymmetry of
the outer arch.That is, the more asymmetric the outer bow, the
greater is the buccopalatal movement of the distalized molars.

Haack &Weinstein AJO 1958:
Fundamental principle involved in the distribution of the forces to
the right and left molars is the geometry of the direction of the right
and left forces emanating from the cervical elastic band.

If these forces are symmetrical with reference to the mid-sagittal line of the
head, then the distribution of the reactionary forces at the right and left
molars will be equal, irrespective of the design of the rigid portions of the
appliance (or the point of attachment of face-bow to arch wire).
If the direction of forces from the cervical elastic band is asymmetrical with
respect to the mid-sagittal line of the head, then the anterior-posterior
components of the reactionary forces on the right and left molars will be
unequal, the molar nearest the resultant of the two elastic band forces
receiving the greater force.
Small lateral forces on the molars are always developed by this eccentric
design

ASYMMETRIC HEADGEAR
5 types of unilateral face-bow designs are available-
• Power-arm face-bow: In this design, one outer bow is longer
and or wider than the other, with the longer or wider bow tip
located on the side anticipated to receive the greater distal
force.
• Tends to generate lateral forces which tend to move favored
molar into lingual cross bite and other into buccal cross-bite.
• Contradicting views on lateral forces.

• Soldered-offset face-bow: In this outer bow is attached to
the inner bow by a fixed soldered joint placed on the side
favored to receive the greater distal force.
• Soldered offset face-bow is not effective in delivering
unilateral distal forces, nor will it deliver a net lateral force to
its inner-bow terminals.

• Swivel-offset face-bow: a swivel joint located in
an offset position on the side favored to receive
the greater distal force.

• Baldini, Nobel and Waters, Hershey et al., have reported
that lateral forces are developed unavoidably.
• But in contrast, Jacobson has demonstrated
experimentally that the swivel offset face-bow provides
the most satisfactory asymmetric force delivery without
undesired lateral components.

• Spring-attachment face-bow: In this, the coil is placed
distal to the stop on the side favored to receive the greater
distal force.
• This design of face-bow were found to be non-effective in
delivering clinically significant unilateral distal forces

• Internal Hinge Facebow-It has hinge added mesial to the
molar on the side not to be distalized and the external arm
is also shortened on the same side.
• The internal hinge face-bow has proved to be remarkably
effective in achieving asymmetric distalization of the
molars

• In contrast to the other designs of facebows, internal
hinge face-bow shows lingual displacement of the
molar on the light force side.
• It may be due to the effect of the internal hinge placed
on that side which limits buccal expansion on that side.
But on the heavy force side, lingual displacement is
more prominent than other facebow designs.
• So, the risk of development of posterior cross-bite is
more on the heavy force side.

LIMITING LATERAL FORCE:
• When the power arm face-bow is reversed, with longer or wider
outer bow on the Class I side and shorter outer bow on Class II side, it
produces a buccal force on the molar that should be more distalized
and thus, preventing crossbite.
• Some authors have even suggested using transpalatal bar in
association with headgear for avoiding excessive lateral forces.
Distal toein bend can be added on the side of the palatal arch where
molar distalization is not desired so that mesial force produced by
palatal arch can counteract distal force generated by reversed power
arm face-bow

• Then equal and opposite distal forces are developed on the other
end of the palatal arch with desired buccal force
• It can be concluded that the asymmetric headgear are effective in
delivering unilateral distalization of molars.
• Among various modification of the headgear, power –arm facebow
is the most effective design for delivering unilateral distal force. It is
very simple in design and easy to fabricate.
• Though lateral displacing forces are unavoidable, it can be limited
by altering the inner and outer bow configuration and also by using
transpalatal bar along with headgear.

Direction of Headgear Force
Given by the line of action of force from the point of origin to the point
of application of force.
Antero-posterior Plane:
a) Force directed upwards above the occlusal plane has an intrusive
effect on maxilla.
b) Force directed downwards below the occlusal plane has an
extrusive effect on maxilla.
c) Force passing along Center of Resistance produces translation

d) Force away from center of resistance( mesially, distally, apically,
occlusally) produces a moment tending to change the occlusal cant.
e) Magnitude of moment is determined by moment arm- Greater the
moment arm – closer the Center of rotation moves towards center of
resistance and greater is the moment.
f) Medium length of outer bow is chosen for translation.
g) Short / long outer bow chosen when moment is desired

Vertical Plane:
a) Direction determined by the sense of the line of action.
b) Outer bow along the Center of resistance produces
translation.
c) Force apical / occlusal to center of resistance produces
moment ( Extrusive / intrusive / distal).
d) Magnitude dependent on the inclination of line of action.

Timing Of HeadgearTreatment
The most optimum treatment time is between maturational stages
SMI 4 to 7, a very high velocity period of growth.
The next most desirable time to treat is during the accelerating
velocity period between stages SMI 1 to 3
The least desirable time is during the decelerating velocity period
between maturational stages SMI 8 to 11

Duration of Force
Intermittent force for 12 – 14 hrs in preadolescent age from early
evening until next morning.
Typical duration of treatment of about 12 to 18 months, depending
on rapidity of growth and patient cooperation.

CLINICAL APPLICATION OF
HEADGEAR FORCE

• In class II extraction cases- prevent molar moving mesially when
anteriors retracted.
• Counteracts side effects of Intraoral mechanics by preventing-
(occipital headgear used)
– Extrusion of molars
– Root buccal-crown lingual moment producing lingual crossbite
• Also can maintain 1st molar width when used along withTPA

• The reaction force from headgear is dissipated against the bones
of the cranial vault, thus adding the resistance of these structures
to the anchorage unit.
• The only problem with reinforcement outside the dental arch is
that springs within an arch provide constant forces, whereas
elastics from one arch to the other tend to be intermittent, and
extraoral force is likely to be even more intermittent.

Magnitude of Force
When line of action is closer to center of resistance greater force of
350 – 450 gms may be applied for orthopedic changes.
Forces away from center of resistance that produce a moment should
be restricted to 50 – 150 gm as in J – hook headgear to prevent
damage to periodontium during dento-alveolar changes that take
place during a moment.

TOOTH MOVEMENT
• If level of outer bow adjusted such that horizontal forces passes
through CR & pt wears headgear 14hrs/day – molar move distal tipping
• 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. Full time wear is necessary.
If 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

ORTHOPEDIC CHANGES
• If headgear force passes through CR of maxilla- in
preadolescent period can prevent forward maxillary
growth.

CONTROLLING CANT OF OCCLUSION
• J-Hook headgear-
– If anteriors extruded- steepen occlusal plane
– If anteriors intruded- flatten occlusal plane
• Cervical pull headgear-
– Extrude molars & flatten occlusal plane.
• High pull headgear-
– Intrude molars & steepen occlusal plane

EFFECT OF TREATMENT WITH
HEADGEAR

TREATMENT EFFECTS
• Extraoral traction has been shown to produce a variety of
skeletal and dentoalveolar 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.

Duration of Force
Many authors have suggested, extraoral appliances should
be worn for about minimum 12-14hrs/day

ANTEROPOSTERIOR DIMENSION
• Maxillary Skeletal Position
A primary treatment effect of extra-oral traction is the restriction of maxillary
skeletal growth.There is virtually 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.

• Distal movement of the maxillary molars is a typical treatment
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 mandibular dentition
other than the treatment effects that are produced in
association with fixed appliance treatment. There appears
to be no effect.

• The anteroposterior relationship of the chin has been correlated to
the amount of vertical opening produced during treatment. A
downward and forward 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.

• Commonly calledACCO appliance.
• AC – Acrylic
• CO – Cervical OccipitalAnchorage.
• A removable plate is used to distalize maxillary molars
bodily. During 2nd phase during which space consolidation
occurs, extraoral forces help maintain anchorage
posteriorly.

• Lateral springs are added to aid distal movement of molars and
occlusal coverage can increase the resistance to dislodgement of
extraoral traction
• This appliance was later modified by addition of 1mm buccal tubes
to labial wire and soldering them vertically at canine-lateral incisor
to receive j-hook and addition of inclined plane to avoid retrusion

HEADGEAR WITH ACTIVATOR:
– Reported by Stockli +Teuscher (1964) wherein a
cervical HG was attached to upper molars.
– 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.

– Primary treatment objective is to
restrict 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 gms/side.

First described by wherein
the headgear is fixed to a tube soldered to the
molar attachment.
High-pull force direction using 1000 gms/side of
force and worn for 12-18 hrs/day in mixed
dentition period.
Produces a synergistic effect on correction of
skeletal Class II cases wherein the Herbst
Appliance stimulates mandibular growth while
this headgear force redirects maxillary growth.

Headgear WithTwin Block
A functional orthopedic appliance system ,W. J. Clark, Am. J. Orthod. Dentofac. Orthop.
THE CONCORDE FACE-BOW
The twin block technique uses a new method of applying inter-
maxillary traction.
The Concorde facebow combines intermaxillary and extraoral traction
by the addition of a recurved labial hook to a conventional face-bow.
Intermaxillary traction is applied as a horizontal force from the labial
hook to the lower appliance, eliminating the unfavorable upward
component of force associated with conventional intermaxillary
traction.

MILLSVIG APPLIANCE
Consists of an active expansion plate with a jack-screw to
eliminate maxillary narrowing and crossbite.
Soldered buccal tubes to molars receive face-bow end.

COMPARISON WITH
FUNCTIONAL APPLIANCES

Tulloch JF, Proffit WR, Phillips C Outcomes in a 2-phase randomized clinical
trial of early Class II treatment. (Am J Orthod Dentofacial Orthop. 2004)
• In a 2-phased, parallel, randomized trial of early (preadolescent)
versus later (adolescent) treatment for children with severe (>7
mm overjet)Class II malocclusions.
• Favorable growth changes were observed in about 75% of
those receiving early treatment with either a headgear or a
functional appliance. After a second phase of fixed appliance
treatment for both the previously treated children and the
untreated controls, however, early treatment had little effect
on the subsequent treatment outcomes

• This suggests that 2-phase treatment started before
adolescence in the mixed dentition might be no more
clinically effective than 1-phase treatment started during
adolescence in the early permanent dentition.
• Early treatment also appears to be less efﬁcient, in that it
produced no reduction in the average time a child is in ﬁxed
appliances during a second stage of treatment, and it did
not decrease the proportion of complex treatments
involving extractions or orthognathic surgery.
Tulloch JF, Proffit WR, Phillips C Outcomes in a 2-phase randomized clinical trial of early
Class II treatment. (Am J Orthod Dentofacial Orthop. 2004)

Stephen D. Keeling Anteroposterior skeletal and dental changes after early
Class II treatment with bionators and headgear (Am J Orthod Dentofacial
Orthop1998)
• Both bionator and head-gear treatments corrected Class II
molar relationships, reduced overjet and apical base
discrepancies, and caused posterior maxillary tooth
movement.
• The skeletal changes, largely attributable to enhanced
mandibular growth in both headgear and bionator
subjects, were stable a year after the end of treatment,
but dental movements relapsed.

A prospective randomized clinical trial was conducted to evaluate the
early treatment of Class II, Division 1 malocclusion in pre-pubertal
children. Facial and occlusal changes after treatment with either a
headgear or a Frankel function regulator were reported.
The results indicate that both the headgear and function regulator
were effective in correcting the malocclusion
Headgear versus function regulator in the early treatment of Class II, Division 1 malocclusion:
A randomized clinical trial J. Ghafari,F. S. Shofer, U. Jacobsson Hunt, D. L. Markowitz, and L. L.
Lasterb

FACE MASK / REVERSE /
PROTRACTION HEADGEAR

• Headgears are generally used for the purpose of
reinforcement of anchorage or for maxillary
distalization. However, when an anterior protractory
force is required, a protraction head gear is used.

• Hickham claims he was the first to use a reverse head
gear. However, this modality was made popular by
Delaire around the same time.
• A reverse pull head gear basically consists of a rigid
extra-oral framework which takes anchorage from the
chin or forehead or both for the anterior traction of the
maxilla using extra-oral elastics which generate large
amounts of force upto 1 Kg or more.

• It can be used in a growing patient having a prognathic mandible
and a retrusive maxilla.
• It can also be used for selective rearrangement of the palatal
shelves in cleft patients.
• It can be used in correction of post surgical relapse after osteotomy.
• It can be used to treat certain accessory problems associated with
nose morphology such as lateral deviations.

• Sites of anchorage-
– Anchorage from skull (forehead)
– Anchorage from chin
– Anchorage from chin & forehead

BIOMECHANICAL CONSIDERATIONS
Amount of force: The amount of force to bring about skeletal changes
is about 1 pound (500 gms) per side.
Direction of force: Most authors recommend 15-20 degree downward
pull to the occlusal plane to produce a pure forwardTranslatory
motion of the maxilla.
Duration of force- Low forces (250 gm/side) take 13 months to
produce desired results. However, very high force values like 1600-
3000 gms reduced treatment time to 4 – 21 days.
Frequency of use: Most authors recommend 12-14 hrs of wear a day.

• Parts of a reverse pull head gear
– Chin cup
– Forehead cap
– Intra-oral appliance
– Elastics
– Metal frame

• FACEMASK OF DELAIRE : This was popularized by
Delaire in the 60's and also uses the chin and forehead
for support.

• TUBINGER MODEL:
 This is a modified type of Delaire face
mask.
 It consists of a chin cup from which
originates two rods that run in the
midline and is shaped to avoid the
interference of nose.
 The superior ends of the two rods house
a forehead cap from which elastics
encircle the head. In addition, a cross bar
extends in front of the mouth which can
be used to engage elastics.

PETITTYPE OF FACE MASK :
 This is also a modified form of Delaire
face mask.
 It consists of a chin cup and a forehead
cap with a single rod running in the
midline from forehead cap to chin cup.
 A cross bar at the level of the mouth is
used to engage elastics.
 The advantage of this model is that the
forehead cap, chin cup and the cross bar
can be adjusted to suit the patient.

HEADGEAR
BY
DR RANJITHAG
1ST YEAR POST GRADUATE
DEPTOF ORTHODONTICS AND DENTOFACIALORTHOPEDICS

SAFETY ISSUES
• Injuries have been reported with the use of headgear.They have
been associated with the catapult effect of simple elastic extra
oral traction and with the face bow coming out at night.
• In some cases, facebow either was knocked, pulled out of molar
tubes while still attached to headstrap or neckstrap.This lead
facebow to recoil and hit patient in face, head or neck.
• This detachment and injuries can compromise success of
treatment.
R H A Samuels, N Brezniak. Orthodontic facebows-safety issues and current management. Jr
Orthod 2002;29:101-7

• Injuries have occurred with both removable & fixed appliances.
• Ranged in severity from minor lacerations to loss of eye.
• All occurred in children aged between 9-14 yrs.
• The presence of oral micro-organisms on the ends of inner bow
radically alters the outcome of the soft tissue trauma, making the
patient highly susceptible to infections.
R H A Samuels, N Brezniak. Orthodontic facebows-safety issues and current management.
Jr Orthod 2002;29:101-7

Samuels RHA, Jones ML. Orthodontic Facebow injuries and safety equipment. Eur J Orthod
1994; 16: 385–394.
• The ends of the inner bow are the same distance apart as the
eyes, increasing the risk of a bilateral injury .

• Facebow injuries to eye can cause little pain at the outset often
delaying the child seeking treatment
• This delay allow infection to proceed unchecked for a considerable
period of time.
• Eyeball is also an excellent culture medium, and when it becomes
infected it becomes difficult to control.
• When one eye is injured there is a risk to the other undamaged eye
from a process called sympathetic opthalmitis.
Samuels RHA, Jones ML. Orthodontic Facebow injuries and safety equipment. Eur J Orthod
1994; 16: 385–394.

Group 1:
1. The patient was wearing their extra-oral traction while playing and
accidentally their hand knocked the facebow out of the buccal tubes and
the elastic traction caused it to recoil back causing a soft tissue injury.
2. The patient removed the facebow from their mouth without ﬁrst
disconnecting the elasticated traction and lifted the facebow up in front of
their face to remove it. On one occasion the facebow slipped from their
hand and the ends of the inner bow caused a facial injury.
3. The facebow was pulled out of the buccal tubes in the patient’s mouth by
another child and then released allowing the facebow to catapult back and
cause a soft tissue injury.
Orthod 2002;29:10

Group 2
The second cause has been due to the facebow coming out of
the buccal tubes at night while the child was asleep and
inadvertently the child has rolled onto the facebow and been
injured by the ends of the inner bow
Orthod 2002;29:10

• In order to prevent these injuries – several safety devices.
• These include self releasing extra oral traction systems,
plastic neck straps, shielded facebows and locking
facebows.
• Patients should be instructed on proper use of appliance.

–
• Manufactured in a variety of designs.
• Modular systems can be used with Headcap or neckcap.
• These modules enable a comfortable range of head movement by
patient without their unintentional release.

A short travel with a suitable force should avoid the recoil injuries
of accidental disengagement, incorrect handling, or undesirable
disengagement by another child. However, it will not counter the
problem of unintentional release during sleep.
The self-releasing extra-oral traction systems can reduce the
catapult effect to approximately 10 mm for the headcap and 25
mm for the neck strap, but cannot be relied upon to keep the
facebow in place at night.

• Plastic neckstraps – Retain facebow within buccal tubes..
• As the strap is not flexible it cannot accommodate the
changing distance between the back of neck and the
facebow, and still provide a continuous resistance to the
displacement of face bow from buccal tubes.

• Shielded facebows – Shielding on their inner ends in an
attempt to reduce the severity or risk of soft tissue trauma.
• Shielding does not improve facebow self retentive capability
and it can disengage in night.
Orthod 2002;29:10

Locking orthodontic facebows –
To maintain the facebow reliably within the buccal tubes at night would
require an alteration to the standard facebow or the buccal tubes to
provide some active self-retentive capability
The Nitom facebow was designed to be used with a self-releasing
headcap or neckstrap with a short travel. It has bilateral locking catches
designed to resist light and medium displacing forces, and can be used
with ﬁxed ,functional and removable appliances. It has two omega
bends so that it can be easily adjusted to ﬁt different lengths of buccal
tubes.

PATIENTS INSTRUCTIONS –
1. Never wear headgear during playful activity.
2. If it ever comes off at night or there are any other problems patient
should stop wearing the appliance and return to see clinician.
3. Excessive force should not be used while removing facebow.
4. Before removing facebow patient first must remove headcap/
neckstrap.
5. If any injury occurs to eye, eye should be examined without delay by
a suitably trained medical practitioner.
Orthod 2002;29:10

Penetrating eye injury from orthodontic headgear-
A case report
Sara Booth- Mason and David Birnie, 1988
A case report of a severe penetrating ocular injury, which resulted in
the loss of the injured eye, following dislocation of a Kloehn bow from
an upper removable appliance is reported.
The case is unusual in that the injury occurred while the patient was
asleep and was probably not due to a catapult injury; in addition the
patient unexpectedly developed sympathetic ophthalmitis in the
uninjured eye.

An 8-year-old child who was trying to remove the facebow by
pulling it out of the buccal tubes and passing it over her head whilst
still connected to the elastic traction, inadvertently allowed the
facebow to slip and it penetrated the left eye. Despite treatment the
eye was lost (De Leo and Bertele, 1992).
A 13-year-old girl who was wearing her headgear whilst playing: it
accidentally became dislodged from her mouth and struck her in
both eyes. Despite treatment she became blind in the right eye and
suffered some permanent visual impairment of the left (Holland et
al., 1985).

PATIENT COMPLIANCE
• An important aspect of using extra oral traction is
whether appliance is being worn as instructed.
• Patient’s compliance can be improved if both parents &
clinician provide motivation.

Conventional measuring instruments to indicate headgear co-operation,
such as
(1) Molar mobility,
(2) Cleanliness of headgear tubes and headgear strap,
(3) Ease of placement by patient,
(4) Space creation between teeth,
(5) Molar positioning comparing pre-treatment models and/or
cephalograms, and
(6) Anchorage maintenance.
Cenk Doruk, Ug˘ur Ag˘ar and Hasan Babacan,The role of the headgear timer in extraoral co-
peration, European Journal of Orthodontics 26 (2004) 289–291

Direct Measurement Of Headgear
Compliance- Headgear Timing
Devices
• The first reported use of a headgear timing device was by
Northcutt in 1974.
• He reported on the first commercially available headgear
timer manufactured by the Aledyne Corporation.

Selçuk type headgear-timer (STHT) was introduced by
Enis Guray 1997
The Selçuk type headgear timer was reported to be 100% accurate,
unaffected by intensity of force variables, reliable, easy to construct,
safe, and inexpensive.
Clinical tests showed a significant increase in headgear wear. An
objective appraisal of extraoral force affects is enhanced by having a
validating measurement of actual appliance wear.

SELÇUKTYPE HEADGEAR-TIMER (STHT) ENIS GÜRAY, AJO
1997

• Wieslander and Buck studied the stability of cervical traction 6 years post
treatment and found that maxillary downward and forward growth
continued equally in both treated and untreated group. A minor tendency
towards relapse was noted.
• Melsen, however by means of metallic implant found that maxillary growth
was greater in treatment group than expected during normal growth.
• Glenn and coworkers found class II malocclusion with large ANB values and
short mandibular lengths were associated with increased incisor
irregularity, shorter arch lengths and deeper overbites at post retention
stage.

• Elm and coworkers found that treatment effects were
relatively stable at 8 years post treatment, with major long
term changes related to those patients who had excessive
amount of tooth movement during treatment.
• Birte Melsen ( AJO 1978) have reported that influence of
headgear on growth pattern of facial skeleton was reversible.

The long-term stability of Class II, Division 1 nonextraction therapy,
using cervical face-bows with full fixed orthodontic appliances was
evaluated for 42 randomly selected patients.
Pre-treatment records were taken at a mean age of 11.5 years; the
post-treatment and post-retention records were taken 3.0 and 11.6
years later, respectively.
The results showed that the ANB angle decreased 2 ° during
treatment, most of which was due to the decrease of the SNA angle.
T. N. Elms, P. H. Buschang, and R. G. Alexander, Long-term stability of Class II, Division
1, nonextraction cervical face-bow therapy: Am J Orthod Dentofac Orthop 1996;109:386-92.

The mandibular plane angle was not changed significantly during
treatment. Although upper incisor inclination was maintained during
treatment, the lower incisor was proclined and the lower molar was
tipped back.
It is concluded that non-extraction therapy for Class II malocclusion
can be largely stable when the orthodontist ensures proper patient
selection and compliance and attains treatment objectives.
T. N. Elms, P. H. Buschang, and R. G. Alexander, Long-term stability of Class II, Division
1, nonextraction cervical face-bow therapy: Am J Orthod Dentofac Orthop 1996;109:386-92

Retention Following Headgear
Treatment
• For patients treated with headgear, the headgear itself may be the best
form of retention until such time that fixed appliances can be used.
• An appliance routinely used to hold the retracted maxillary molars is the
Nance holding arch.The Nance appliance is not as effective in holding the
molars back in the maxilla as the fixed lingual arch is in maintaining E-space
in the mandible.
• A modified Nance holding appliance, the vertical holding appliance (VHA),
may be more successful in such instances since the force exerted by the
tongue is vertical and directed to the posterior.

• The effects of two different extraoral appliances were evaluated
over a 1-year period. Of the 37 cases selected for study, twenty were
treated with a face-bow neck strap and seventeen were treated
with a high-pull molar headgear.
• Patients ranged in age from 10.10 to 16.6 years and averaged 13.4
years.The appliances exerted less than 600 Gm. of force per side
and were worn for 12 to 16 hours per day. All cases were fully
banded, and extraction and non-extraction treatment were
included.
Brown P 1978 A cephalometric evaluation of high-pull molar headgear and facebow neck
strap therapy, American Journal of Orthodontics 74 : 621 – 63

The comparison of the two treatment samples revealed that the
functional occlusal plane was tipped down at the back as the
maxillary molars were more extruded in the neck strap sample. In the
high-pull sample, the functional occlusal plane was unchanged and
the mandibular molars were more extruded than they were in the
neck strap group.

Vertical relationships provide the key to planning treatment for the
individual patient. When vertical growth is judged to be adequate
or excessive ,the high-pull molar headgear is the therapy of choice
to inhibit further vertical development.
In cases exhibiting a deficiency of vertical growth, face-bow neck
strap traction may be employed to encourage vertical
development.

The present study aimed to evaluate the cephalometric changes in
Class II patients treated exclusively with cervical headgear (CHG) in
the maxillary arch and fixed appliances in the mandibular arch as
compared with a control group.
The sample comprised 82 lateral cephalograms obtained pre- (T1) and
post- (T2) treatment/observation of 41 subjects, divided into two
groups:
M. R. Freitas , D.V. Lima , K. M. S. Freitas , G. Jansonand J. F. C. Henriques, Cephalometric
evaluation of Class II malocclusion treatment with cervical headgear and mandibular fixed
appliances, European Journal of Orthodontics 30 (2008), 477–482

Group 1 — 25 Class II division 1 patients (20 females and fi ve males),
with a mean pre-treatment age of 10.4 years, treated for a mean
period of 2.5 years
Group 2 — 16 Class II untreated subjects (12 females and four males),
with a mean initial age of 9.9 years, followed for a mean period of 2.2
years.
The results showed restriction of maxillary forward displacement and
also a restriction in maxillary length growth, improvement in the
maxillomandibular relationship, restriction of mandibular incisor vertical
development, reduction in overjet and overbite, and improvement in
molar relationship.

CONCLUSION
• Extraoral traction has proved to be a dependable method
of class II correction for over 100 years, and this treatment
adjunct is used with varying frequency worldwide.
• When the correct type of extraoral traction appliance is
prescribed for a patient who is cooperative, effective and
efficient treatment is the result. In non-cooperative
patients, however ,alternative methods of class II
correction are indicated

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