Indian Dental Academy Guide to Headgear Types and Uses

INDIAN DENTAL ACADEMY
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Contents
 Introduction
 Evolution of headgear
 Classification of headgear
 Parts of face-bow headgear
 Biomechanics of headgear
 Clinical application of headgear force
 Effect of treatment with headgear

 Clinical procedures for use of headgear
 Management of treatment with headgear
 Various types of headgear in detail
 Conclusion


Introduction


Headgear–
–

Most commonly used orthopedic appliance
Used in orthodontics to modify growth of maxilla, to
distalize & protract maxillary teeth & to reinforce
anchorage.
– When skeletal modification desired- heavier forces
recommended- action on sutures of maxilla- change
direction & magnitude of growth.
– Combined skeletal & dental changes occur
– Various types of headgear available- selection based
on treatment objective.

Evolution of headgear


 Use

of extra-oral force is about 100 years

old.
 The "head cap" was described by Kingsley
in 1866 and Farrar in the 1870's.
 Its objective was limited to retraction of
upper anterior teeth.


 Angle

in 1888, described his extra-oral
attachment.
 The use of this appliance was limited to
maxillary dental protrusion in patients
following upper first bicuspid extraction.
 He recommended it to be worn during the
sleeping hours.


 In

1888 Goddard had described the
making of a Vulcanite casing by molding
black rubber against anterior teeth to
which was attached the head caps of
dress hooks, with rubber elastic bands.
 This was forerunner of head gears
attached to rubber positioner currently
used sometimes.

 In

1898 Guilford talked about direction pull
by activating rubber strands of the "Skull
Cap" above or below the ear.
 He recommended 16 hours of wear and
advocated use of light force and used the
appliance as retainer for 1 year after initial
correction.


 Thus,

up through the turn of the century,
extra oral force was the main source of
retraction of protrusive incisors.
 As orthodontics progressed in the early
twentieth century, however extra oral
appliances and mixed dentition treatment
were abandoned- an unnecessary
complication.

 In

1921, Case had extended the
application of extra-oral therapy.
 He described three different extra oral
applications, all of which employed
"Sliding” buckles for the least possible
discomfort.








1. First, was the usual directional pulls up the
long axis of maxillary anteriors following
maxillary teeth extraction.
2. Second, was an attachment to the lower
anterior to be used in open bites or protrusive
conditions, also after lower teeth extraction.
3. Third, and here is the first mention of upper
molars to be moved distally. The labial bar was
extended to the bicuspid area on the dental arch
wire and forced the molars and entire arch
backwards.

 In

meantime Angle was looking towards
Intraoral or inter maxillary traction (Baker's
anchorage) and was successful.
 Angle and his followers were convinced
that class II and class III elastics not only
moved teeth but also caused significant
skeletal changes.
 Argument - if Intraoral elastics could
produces true stimulation of mandibular
growth while simultaneously restraining
maxilla, then why extra oral appliances.







Cephalometric evaluations which became
available in 1940's did not support the concept
of that significant skeletal changes occurred in
response to Intraoral forces.
Cephalometrics also revealed instability of lower
arch and many found a frequency of producing
protrusive dentures.
Great numbers of clinicians took to extraction
therapy following Tweed in 1936.

 Oppenhein

from Vienna in 1936 reviewed
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.

 The

ones who achieved success were
Silos Kloehn & William B Downs.
 Kloehn went on to combine the dental bow
and face bow in a soldered joint making
the centre apparatus removable.
 By 1950's many still employed the straight
pull head cap described by Kloehn of the
face bow and dental bow of 0.45inch,
extended to molar tubes placed
occlusalward to the edgewise tubes.

 Recognizing

the need for downward pull
at the ends of the outer bow Ricketts
working with Downs applied only the neck
strap portion of the Kloehn head cap.
 This was followed by Downs designing full
elastic neck strap or the cervical
anchorage still popular today.
 Kloehn in the meantime also used only the
neck strap.








Ricketts was surprised at the improvement in
several retrognathic cases with the use of the
high-pull canine headgear.
He noted that the high-pull headgear did not tip
the palatal or occlusal planes the way the
cervical headgear does.
It improved the facial angle, however, whereas
the cervical molar headgear did not.
The directional or developmental behavior of
the chin could be influenced by treatment
techniques.

 Others

came to attaching extra oral
traction to hooks on the arch wires with
anterior teeth banded.
 Some were attached to a neck strap which
elongated the anterior teeth and closed
the bite more severely.
 Others attempted a straight pull of the
arch wire from the head cap, but still used
no face bow.







Still others chose to attach smaller dental bow to
the edgewise arch wire in the bicuspid area and
used the neck or head for anchorage (fisher
1950) as many now use it with full banded
appliance.
Among all these methods, Kloehn approach with
neck strap which he later adopted became the
method of choice.
The benefits of bite plates being used in
conjunction with headgear remained
controversial.

 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.


 In

1967, Cervera modified the face bow
design for the correction of class II, div I.
 Jacobson in 1976 explained the
mechanics associated with headgear
therapy.
 In 1978 Teuscher used headgear with
activators. And subsequently in 1980's
and 1990's many people employed
headgear with their appliances like Clark
with twin block.

 Out of many work

Schudy, Poulton &
Tweed have made greatest contributions.
 Schudy's work has given us an insight into
mechanics of the rotation of the mandible.
He concludes– Orthodontists should investigate ways of
stimulating & inhibiting vertical growth of jaws.
– Facial esthetics significantly affected by
rotation of mandible & degree of facial
divergence.


– Molars of low-angle cases are more difficult to extrude
and molars of high-angle cases are easy to extrude
and once extruded remain so.
– Molars should be extruded in low angle cases but not
in high-angle cases.
– Extrusion of 1st molars by 1 mm opens the chin
approximately by 1.6 mm.
– Too much molar height prevents a forward
positioning of the chin and thereby prevents a
reduction of the ANB angle. This in turn, renders
Class II correction more difficult.

– The condyles continue to grow after cessation of
growth of the maxilla.
– Class II correction is more difficult in high mandibular
plane angles.
– Molar move occlusally easier with a small freeway
space than with a large freeway space.
– Tongue habits may develop through extrusion of
molars.
– Most Class II cases have average horizontal growth
but too much vertical growth.
– Variation in the growth of the condyle and the facial
complex is responsible for the rotation of the mandible
and the size of the gonial angle affects the amount of
rotation.

 In

order to take advantage of these new
concepts of treatment, Schudy and
Creekmore designed a high-pull molar
headgear with the outer bow terminating
at the site of the maxillary first molar.

 They

used this type of headgear in cases
where they did not want to extrude the
molars, such as in cases of open-bite and
high mandibular angles.

 Poulton

has studied occipital headgear
and their line of pull. In 1959 he
designated the geometric center of the
maxilla as the center of resistance, and he
located it between the roots of the
premolars. He observed that the distal pull
the upper dentition should be aligned
through the center of resistance, to avoid
undesirable tipping movements .


Classification of headgear


Acc. To useTo distalize maxillary dentition- face bow
headgear
To protract maxillary dentition- face mask/
reverse headgear


 Acc. To Root (1975) suggested simplified

classification using occlusal plane as
demarcationJ-Hook headgearAttached to teeth
Attached to arch wire
Also further acc. To pull-

High pull

straight pull

low pull


Face bow headgear-

High pull
straight pull
low pull
(occipital/parietal)
(Kloehn type)


 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 between upper lateral incisor
and canine.

 Outer bow-

Made of 1.5 mm stiff round wire contoured to
fit face.
Can be
short
medium
long
Distal end curved to form hook- gives
attachment to force element.

 Inner bow-

– Made of 1.25 mm 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.


 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.

Head cap or cervical strap




Takes anchorage
from rigid skull bones
or back of neck.
Selection based on
pt. needs.


Biomechanics of headgear


Mechanical principles that need to be defined
include the following



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 pt.
– Acc to Worms 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 acc. To no. of teeth banded & size of
their roots.


 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 CRcentre of rotation moves coronally & one gets
counterclockwise moment.
– Vice versa if LOF passes below CR





Moment = T X P
Greater P
greater
moment.


 Force resolution –

resolved into
component vectors at right angles to each
other.


 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 lt. of outer bow varying angle b/w
outer & inner bow


Clinical applications to above principles
 Teeth can be moved in 3 planes of space-

–
–
–

Sagittal
Coronal
Transverse


Sagittal plane
 Studied under-

–
–

Distance of LOF from CR
Inclination of line of force


Distance of LOF from CR
 When passing through CR- no tipping
 When below or occlusal to CR- crown tip

distally & root mesially (clockwise
moment)
 When above CR- root mov. Distally
(counterclockwise moment)


Inclination of line of force
 Depends on-

–
–

Point of origin of force
Point of attachment of force


Point of attachment of force




In sagittal plane can be located along A-P axis
( A represent point of attachment anteriorly of
short outer bow & P represents point of
attachment posteriorly of long outer bow)
Vertically, outer bow hook can be located
anywhere along VV1 axis where V & V1
represents vertical extremities of point of
attachment above & below 1st molar teeth
created by angulation of outer arms of face bow.



Shape of outer bow- no effect on application of
force on molar provided D1=D2


 Point of attachment of outer bow hooks

are variable & may be altered to fit
anywhere in sagittal rectangle by– Varying lt. of outer bow
– Varying angle b/w outer & inner bow


Extrusive & intrusive force components
 If LOF below CR as in cervical tractions-

extrusion
 If LOF above CR as in high pull- intrusion
 Magnitude of intrusive & extrusive force
depends on inclination or steepness of
LOF.
 Steeper LOF, more intrusive or extrusive
force.

Distal force component
 It is maximum when LOF is horizontal

rather than inclined & passes through CR.
– No intrusive or extrusive force
– distal force magnitude = magnitude of force
applied


 Mathemetically –


Translatory, crown or root-tipping movement


Coronal plane
 Molar teeth can be moved vertically

(intruded or extruded) &/or laterally or
medially


Lateral or medial action
 Since buccal tubes of molars located

buccal to CR & below-

– Intrusive force- crown buccally & root lingually
– Extrusive force- crown palatally. Can be
prevented by soldering palatal bar to lingual
aspect of both molars.


Effect on intrusive force


Palatal bar soldered


Transverse plane
 Expansion or contraction of inner arch of

face bow can be done acc. To treatment
need.


Duration, magnitude of force applied
 Duration-

– acc. To clinical experience intermittent forces
very efficient. Ex- effectiveness of thumb
sucking in moving teeth & bone.
– Wear of 12-14 hrs/day sufficient or sometimes
10hrs/day.


 Magnitude –

– Acc to Kloehn & Jacobson- guided by pt
comfort
– Acc to Berman (1976) – 450 gm/side
– J-hook headgear applies- 170-226 gm initially
– Acc to Klein, Poulton, Graber- 450900gm/side
– Should not exceed total of 7 pounds force on
maxilla

 Timing of headgear use- late mixed

dentition period generally before eruption
of permanent canine.


Clinical application of headgear force


Anchorage control
 In class II extraction cases- prevent molar

mov. Mesially when anteriors retracted.
 Counteracts S/E of Intraoral mechanics by
preventing- (occipital headgear used)
– Extrusion of molars
– Root buccal-crown lingual moment producing
lingual crossbite

 Also can maintain 1st

used along with TPA

molar width when


Tooth movement
 If level of outer bow adjusted such that

horizontal forces passes through CR & pt
wears headgear 14hrs/day – molar move
distally 2mm in 24 months without tipping


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


Skeletal effects


Objective of orthopedic treatment–
–
–
–




To compress max. sutures
Alter growth & apposition of bone at sutures
Restrict downward & forward max. growth
Allow normal mandibular growth

Studies shown- small increase in mandibular
growth with headgear
Mainly indicated in case of forwardly placed
maxilla with normal growth potential of mandiblemixed dentition

Dental effects
 Prevent downward & forward eruption of

maxillary molar indirectly enhancing
mandibular growth
 Intrusive effect on molar- high pull
headgear
 Cass where LAFH to increase- cervical
pull headgear to extrude molar.
 Mandibular incisors may protrude



If continues arch wire from molar to incisorsdistal mov. Of molar can result in lingual mov. of
maxillary incisors.



Intrusive & distal force can be applied tom all
erupted teeth if standard face bow attached
directly to maxillary splint or functional
appliance.



J-Hook headgear used- extrusion or intrusion of
incisors depending whether LOF passes above
or below CR.

Clinical procedures for use of headgear


Preparation of dentition
 Fitted to maxillary 1st

molar- if molar M-L
rotated as in class II, insertion of face bow
difficult- short period of ortho treatment
with active TPA to derotate molar
 J-Hook headgear fitted to maxillary
incisors- complete banding & bonding of
maxillary teeth with 17X25” stainless steel
in .018” slot recommended- alignment of
teeth required



Determine CR of body to which headgear to be
attached.



Selection of headgear acc. To pt. need– High pull
– Straight
– Cervical


Various types of headgears selected acc. to pt. need


How the headgear to be applied
 Either to maxillary 1st

molar
 Removable appliance fitted to maxillary
teeth (maxillary splint/functional appliance)
 To archwire anteriorly (J-Hook headgear)


 Decision whether to move teeth bodily or

tip.

 Length & position of outer bow & form of

anchorage determine vector of force & its
relationship to CR


 After deciding which headgear to be used-

– Select preformed face-bow with inner bow
fitting closely to upper arch with contacting
teeth except 1st molar
– Bow should rest comfortably b/w lips
– Extension of inner bow out of 1st molar tubes
to be evaluated- in flush or 1mm pass the
tube
– Inner bow expanded by 2mm symmetricallytendency for crossbite


– Outer bow should rest several mms from
cheek. Mast be cut to proper lt. & hook
formed at the end.
– Lt. & vertical position selected to achieve
correct force direction relative to CR.
– With bow in place, place ur fingers on outer
bow simulating direction of force application at
different points bilaterally.
– If junction lifted up- headgear will move roots
distally & vice versa.
– If not lifted- bodily movement









Spring action strongly recommended to provide
force. Adjusted to deliver correct amt. of forcecheck with pt sitting or standing.
1st start with low force level to acclimate the pt. to
headgear & gradually increase the force. Ideal
force- 350-450gms/side
Child should place & remove headgear under
supervision several times. Headgear strap s/b
equipped with safety release mechanism.
Optimum wear- 12-14hrs/day


Management of treatment with headgear







Pt s/b warned- soreness to be expected during
1st week till supporting bone adapts to force
Next visit after 2wks to verify pt compliance.
Then after 1 month next visit. Frequent visits
increase compliance
No. of indicators to assess headgear wear–
–
–

Ease with which pt can place & remove appliance
Mobility of max. molar
Signs of wear of extra oral attachment components &
calculus on face-bow after few months of wear.
– Improvement in A-P relationship

 Force magnitude decreases after few

months as occipital or cervical attachment
stretches & confirms to pt head or neckincrease force level & adjust its direction
 Adjust inner bow for expansion
 If maxillary molar crowns tipped
posteriorly- raise & shorten outer bow to
direct force above CR
 If molars move distally- necessary to open
vertical adjustment loops to lengthen inner
bow

 Phenomena of pt’s fundamental growth

pattern re-expressing itself following
cessation of orthopedic treatment must be
considered when determining end of
headgear wear.
 To minimize this– Overcorrection
– Continuance of some degree of orthopedic
treatment until maxillary growth is completednightly wear of haedgear.

Various types of headgear in detail


HIGH PULL

STRAIGHT PULL


CERVICAL PULL

Safety bows

Cervical headgear




Also called “Kloehn headgear”- given by Kloehn
in 1953
Used most commonly
Composed of 3 components–
–
–



Molar bands & tubes
Inner bow & outer bow soldered in middle
Neck strap placed around back of neck

Used in early treatment of class II malocclusion
to inhibit forward growth of maxilla






Cause extrusion of molars- desirable in pt with
short LAFH.
If outer bow above CR- counterclockwise
moment
If below CR- clockwise moment but direction of
forces same- extrusive & posterior
Advantageous to be used in treatment of short
face class II maxillary protrusion cases. Cases
with low mandibular plane angles & deep bites
where desirable to extrude upper molars.


 Disadvantage – “cervical face bow

reaction or Kloehn rn.” – extrusion of
maxillary molars cause mandible to be
wedged open when posterior teeth come
into occlusion.
 Barton (1972) estimated- extrusion of
max. molar by 1mm produces 1.6mm
opening anteriorly as mandible rotates
downwards & backwards.


 Occlusal plane tipped occlusally at its

anterior end- upper incisor teeth now to be
retracted further & will require greater root
axial control.
 Pogonion will move downwards &
backwards worsening profile with
prominent nose & increase LAFH.


 Acc to study in AJO 2001-

– Cervical headgear doesn’t cause extrusion of
molars & doesn’t depend on facial type
– Some amt of mandibular rotation noticed0.25 degree
– Post retention period of 6yrs: -1.5 degree but
this reflects inherent growth potential of
individual rather than rebound.


Effect of cervical headgear on pts with high or low
mandibular plane angles & “myth” of posterior
mandibular rotation
AJO 2004;126:310-317


 No difference in FMA changes in 2

groups.
 Structural superimposition of mandible
after treatment showed marked
counterclockwise rotations in relation to
anterior base of skull in 2 groups with high
angle gp rotating less significantly.
 On average, growth & treatment resulted
in improvements in high angle pts but
aggravated problems in low angle pts with
deep bite malocclusions.

 Posterior facial ht found to increase

significantly more in low angled gp.

 Vertical skeletal relationships in growing

face could not be altered predictably by
controlling direction of extra oral forces.


Effect of cervical headgear on C-Axis:
growth axis of dentoalveolar complex
AJO 2004;126:694-698









Headgear worn 8-10hrs/day.
Mean velocity of C-Axis lt. increase in growing
boys- 1.14mm/yr
In girls 1.67mm/yr at age 9 to 0.78mm/yr at 13.5
yrs of age
Cervical headgear reduced C-Axis lt. by 73.7%
in boys & 61.1% in girls.
Growth axis vector angle Q not affected.
But alpha became more acute in both sexes,
rather than becoming obtuse as in normal
growing individuals.

Cervical gear with J-Hooks




Anterior Hooks can sometimes be soldered onto
the stainless steel archwire, which extends from
the first or second molars around to the same
tooth on opposite side.
These hooks are positioned mesial to the
canines on each side. The outer bow in this case
consists of a right and left arm with an eyelet at
the end, which fits over each of the soldered
hooks.





A cervical strap is then fitted to the loops on the
outer bow. This type of headgear is used often in
Class II deep overbite cases.
The reasons and problems with this are-

– It does apply distal force to the upper jaw, correcting
Class II relation.
– It does apply a positive moment tending to steepen
the occlusal plane, making the Class II appear better.
– It extrudes the upper teeth, hinging the mandible open
(Beneficial in horizontal growers). Worsening AB
discrepancy.



Some have modified this and named it as "high
cervical headgear"

High pull headgear
 Produces intrusive & posterior direction of

pull
 Higher pull- more intrusive & less distal
effect
 If outer bow anterior to LFO, either below
or above occlusal plane- counterclockwise
moment
 If placed posterior- clockwise moment

 Beneficial in long-face class II pt with high

mandibular plane angle where intrusion of
molar desired.
 Barton (1972)- high pull headgear with
long outer bow will cause mesial root
tipping- rotating fully banded maxillary
arch, inner end moving occlusally.
Overbite in high FMA, anterior open bite
case might improve.


High pull headgear & cervical headgear:
comparison
AJO 1972;62:517-530


Results








Greater extrusion of maxillary molars with
cervical pull. Chin faced downward- drop down
2.6mm more than high pull
High pull treatment of choice- extrusion of
molars & incisors contraindicated
Cervical- extrusion desired
High pull doesn’t exert sufficient horizontal force
to retract the incisors sufficiently in severe
protrusion.
SNB angle comparison- high pull- mandible
came forward .85 mm more than cervical pull.



Statements regarding molar type of headgear– The position of the tip of the outer bow determines the
line of pull of the molar headgear.
– If the line of pull is in front of & above the CR, the
plane of occlusion will move counterclockwise.
– In closed bite cases with low mandibular plane angle,
the cervical pull headgear indicated.
– In closed bite cases with high mandibular plane angle,
the line of pull s/b directed through or slightly above
CR.
– In an open bite cases, the occipital or high pull molar
is indicated, with line of pull below CR.




Statements regarding canine type of headgear– In closed bite cases the line of pull s/b through or
slightly above CR.
– In an open bite cases, the line of pull s/b below CR.
– In open bite cases, the cervical canine headgear is
the most efficient.
– The straight & occipital canine headgears pull below
the CR, causing a clockwise movement of the plane
of occlusion.
– The position of the arch wire hook & the point of pull
determine the line of pull for the canine headgears.


True Occipital Headgear
 This

headgear consists of a typical face
bow along with variations of occipital
harness.
– Occipital type: This harness is placed around
the ear and can be fabricated in such a
manner that the pull of the elastic straps is
parallel to the plane of occlusion. (pull is
anywhere between high cervical and the top
of the ear)

– Interlandi type: This harness arrangement
consists of an occipito cervical combination
strap along with small E shaped plastic ring
into which are placed small notches for the
elastics. The level of the force is determined
by which of the notches is used to connect the
elastic to outer bow hooks.
– Combee type: These combination type
headgears have both occipital and cervical
traction springs. This is perhaps the most
versatile type because the pull can be
controlled by selecting the force level springs
and by controlling the length of outer bow.

Adjusting Directional Pull of Occipital Headgear to
Upper Arch
 Condition

segment-

1: For distal translation of buccal

– The distal force should pass straight through
CR
– A combination or Interlandi will allow distal
force straight through CR by having equal
occipital and cervical components on an outer
bow, which is angled upward to pass through
CR.



Condition 2: For intrusion of upper anterior
segment

– The undesirable side effects of upper anterior
intrusion is extrusion of molars and steepening of
occlusal plane.
– To prevent these side effects and to provide the
desired action, an upward & backward force is to be
applied anterior to CR of buccal segments.
– This is achieved by using a short outer bow and
occipital pull. The shorter bow produces a negative
moment in buccal segments. The other alternative is
to have a outer bow of length, which makes the force
vector pass through CR then resulting in upward and
backward force (with no moment).


 Condition

maxilla

3: To hold the vertical growth of

– In this force vector has to pass upward
through CR.
– For this, an area of attachment quite anterior
on top of the head is needed.




Condition 4: Upper posterior segment
steepening of occlusal plane (in open bite
cases)
– When a force vector passes posterior to CR it
produces a positive moment thereby steepening the
occlusal plane.
– With a occipital harness and force vector lying
posterior, can be obtained by placing the outer bow
posterior to CR (long outer bow).



The advantage of this type of headgear is
– It causes steepening of occlusal plane as a virtue of
+ve moment.

Straight pull headgear
 Location of LFO can be changed.
 Prime advantage- pure posterior

Translatory force by placing LFO through
CR, parallel to occlusal plane.
 Advantageous in class II malocclusion
with no vertical problems. Also headgear
of preference when main thrust of
headgear wear is to prevent anterior
migration of maxillary teeth.

Acc to AJO 1998;113:317
 Various directed forces applied by

combined headgear evaluated in the
study– 1st treatment gp- forces of 150gm/side for high
pull & cervical component
– 2nd treatment gp- 200gm/side for high pull &
100gm/side for cervical
– 3rd treatment gp- 100gm/side for high pull &
200gm/side for cervical

Results
 Intrusion of upper molar in 2 nd

treatment gp
& extrusion in 3rd treatment gp
 Acc to Brown- cervical pull more effective
in reducing ANB than high pull
 Evaluation of superimposition- upper 1 st
molar distalized by 3.6-4mm
 Mandibular plane angle- significant
decrease in 2nd treatment gp when
compared to 3rd.

 Occlusal plane inclination- 1st

& 2nd
treatment gp showed significant increase
when compared to 3rd.
 Distal tipping of upper molar in 3 rd
treatment gp- significant
 Acc to Baumrind et al- horizontal
displacement of 1st molar greater in high
pull than cervical pull. But in this study no
significant differences b/w gps.


Vertical pull headgear
 To produce intrusive direction of force to

maxillary teeth with posteriorly directed
forces.
 If outer bow hooked to headcap so that
LFO is perpendicular to occlusal plane &
through CR- pure intrusion
 Head divided into 2 compartments– Anterior- from LFO forward
– Posterior- behind LFO


 If outer bow placed anywhere in anterior

compartment- counterclockwise moment,
intrusive & posterior force
 If outer bow in posterior compartmentclockwise moment
 Useful in class I open bite cases for pure
intrusion of buccal segments.


J-Hook headgear






Attached to arch wire- hooks distal to LI- places
intrusive & distal force upon incisors if LFO
above CR. Also crown tips labially.
Hook can also be placed b/w CI & LI for better
intrusion effect.
Can be used to retract & intrude upper anteriors.
Can help in distal mov. Of canines or to sliding
jigs for maxillary molar distal mov.




Used in Tweed mechanics effectively for
retraction of upper anteriors & to counteract
extrusive effect of class II elastics on anterior
teeth.



Low pull J-Hook headgear- tipping of incisal end
of occlusal plane in downward directionreduction in open bite



Low pull when used in mandibular incisor areamay depress chin creating more vertical space
into which maxillary teeth may be extruded
during class III treatment. Resultant backward &
downward mandibular rotation reduces A-P
discrepancy.

Asymmetric headgear
 Experiments conducted to see effects of

various asymmetric headgear & symmetric
one


 2 symmetric headgears tested-

1 having
narrow inner arch with more or less
parallel distal ends & 2nd having wide inner
arch with divergent distal ends. Inner bows
properly contoured to confirm dental
arches.
 Results– Face bow in which anterior section of inner
arch was stiffened or reinforced by adding of
tubing- showed o discernible molar expansion
with application of 3pds of force/side



To test face bow with
soldered joint off
centered. Face bow
designed to exert
more distal force on
side of solder joint.


 Forces upon molars using

symmetrically
soldered outer bow, arms of which were of
different lts.
 2nd part- bending longer arm away from
cheek & measuring effect of applying extra
oral force to these hooks.


 Swivel type of unilateral extra oral face

bow tested- provided most satisfactory
unilateral force delivery without usual
accompanying lateral component to both
molars.


Swivel type

Face mask / reverse / protraction headgear
 Head

gears are generally used for the
purpose of reinforcement of anchorage or
for maxillary distalisation. 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 extraoral elastics which generate large amounts of
force upto 1 Kg or more.

Indications







It can be used in a growing patient having a
prognathic mandible and a retrusive maxilla.
It can be used for bending the condylar neck for
stimulating TMJ adaptations to posterior
displacement of the chin.
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 (450 gms) per side.
Direction of force: Most authors recommend 15-20
degree downward pull to the occlusal plane to produce a
pure forward Translatory 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


Types of reverse pull head gear
 Protraction

head gear by Hickham :

– Developed in the early 60’s.This appliance
uses the chin and top of the head for
anchorage.
– Force distribution is as follows - 15% head,
85% chin
– The advantages of the appliance include
relatively better esthetics and comfort than
others with the option of unilateral force
applicability.




Facemask of Delaire :
This was popularized
by Delaire in the 60's
and also uses the
chin and forehead for
support (fig 4).


 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.

 Petit

type 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.

Long term effects of headgear







Tuenge and Elder observed reversal of bone to
original position 6 months after removal of high pull
headgear.
Jackson found the relapse was proportional to the
length of the retention period. The slow skeletal
changes produced less relapse. Long term stability is
influenced by tissue elastic recoil and remodeling of
bones.
Storey demonstrated that the quantity and quality of
bone are important for prevention of relapse.
The reaction forces are stored in the skull that tend to
induce relapse for at least 6 weeks after the removal
of headgear.

 If

no retention is provided during this
period, sutures being adaptive structure,
will cause the bones to return to the
original position.
 Proper occlusion is found to reduce the
relapse tendency.


Conclusion
 The objective in treatment of class II

malocclusion in late mixed dentition is to
establish normal occlusion & normal m.
balance by distal bodily mov. Of upper 1 st
molars & incisors, along with associated
remodeling of maxillary alveolar process in
direction of tooth mov.


 The establishment of normal m. balance is

consistent with theory of “functional
matrix” in growth & restoration of normal
occlusion enhances ability of upper &
lower jaws to grow downward & forward
together- headgear is one of means to
achieve this but proper application of force
& in correct direction acc. To treatment
need required.


Thank you
Leader in continuing dental education


Indian Dental Academy Guide to Headgear Types and Uses

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