Maxillary protraction in orthodontics

Maxillary protractionMaxillary protraction
inin
OrthodonticsOrthodontics
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IntroductionIntroduction
 Orthodontic treatment not only involvesOrthodontic treatment not only involves
establishment of physiologically andestablishment of physiologically and
anatomically functional occlusion but alsoanatomically functional occlusion but also
envisages correction of the relationship ofenvisages correction of the relationship of
the maxilla and mandible to each otherthe maxilla and mandible to each other
and to the rest of the craniofacial complex.and to the rest of the craniofacial complex.

 To achieve a harmonious dentofacialTo achieve a harmonious dentofacial
relationship as a result of orthodonticrelationship as a result of orthodontic
treatment, extraoral devices using thetreatment, extraoral devices using the
neck or cranium as anchorage have beenneck or cranium as anchorage have been
employed since the turn of the century.employed since the turn of the century.
 These extraoral appliances have beenThese extraoral appliances have been
used to influence the maxillary andused to influence the maxillary and
mandibular growth patterns by inhibitingmandibular growth patterns by inhibiting
and/or redirecting their normal growthand/or redirecting their normal growth
potentials in children before and duringpotentials in children before and during
maximal pubertal growth.maximal pubertal growth.

It is generally agreed byIt is generally agreed by
orthodontists that skeletalorthodontists that skeletal
Class III malocclusions areClass III malocclusions are
difficult to treat by orthodonticdifficult to treat by orthodontic
means alone.means alone.
A skeletal class III discrepancyA skeletal class III discrepancy
may be the result of a largemay be the result of a large
mandible, a small maxilla, amandible, a small maxilla, a
distally positioned maxilla, ordistally positioned maxilla, or
any combination of the three.any combination of the three.
Most often the patients areMost often the patients are
advised to wait until theadvised to wait until the
termination of active facialtermination of active facial
growth so that maxillofacialgrowth so that maxillofacial
surgery can be performed.surgery can be performed.www.indiandentalacademy.comwww.indiandentalacademy.com

 Orthopedic protraction of underdevelopedOrthopedic protraction of underdeveloped
or retrognathic maxillae is one of the majoror retrognathic maxillae is one of the major
objectives in the treatment of certainobjectives in the treatment of certain
skeletal Class III malocclusions.skeletal Class III malocclusions.
 Maxillary protraction methods haveMaxillary protraction methods have
included chin cup and spurs, combinedincluded chin cup and spurs, combined
head cap and chin cup, "pull-down" facialhead cap and chin cup, "pull-down" facial
mask, chin cup and labial facebow,mask, chin cup and labial facebow,
football helmet, palatal expansion andfootball helmet, palatal expansion and
Class III elastics, and facial mask withClass III elastics, and facial mask with
forehead and chin support.forehead and chin support.

HistoryHistory
 The use of a protraction face mask wasThe use of a protraction face mask was
first described more than 100 yrs agofirst described more than 100 yrs ago
potpeschnigg 1875.potpeschnigg 1875.
1944, Oppenheim reported that it is
impossible to move the mandible
backward, but that it is possible to bring
the maxilla forward to compensate for
mandibular overgrowth when treating
Class III malocclusions.

 In the 1960’s Delaire &others revived theIn the 1960’s Delaire &others revived the
interest in using a face mask for maxillaryinterest in using a face mask for maxillary
protraction.protraction.
 Petit (1983)modified Delaire’s basic conceptPetit (1983)modified Delaire’s basic concept
by increasing the amount of force generated byby increasing the amount of force generated by
the appliance.the appliance.
 In .1987 Mcnamara introduced the use of aIn .1987 Mcnamara introduced the use of a
bonded expansion appliance with acrylicbonded expansion appliance with acrylic
occlusal coverage for maxillary protractionocclusal coverage for maxillary protraction

Nanda introduced a modified protraction
headgear face bow that aimed to control the
point of force application and direction of the
force. The forehead and the chin were used as
areas of support.

 Turley improved patientTurley improved patient
cooperation in wearing thecooperation in wearing the
appliance by fabricatingappliance by fabricating
customized face masks.customized face masks.

Cases suitable for face maskCases suitable for face mask
 Mild to moderate skeletal class III malocclusionsMild to moderate skeletal class III malocclusions
with a retrusive maxilla & a hypodivergentwith a retrusive maxilla & a hypodivergent
growth pattern.growth pattern.
 Patient with anterior mandibular shift & aPatient with anterior mandibular shift & a
moderate overbite have a more favorablemoderate overbite have a more favorable
prognosis.prognosis.
 Patient with hyperdivergent growth pattern & aPatient with hyperdivergent growth pattern & a
minimal overbite ,a bonded acrylic palatalminimal overbite ,a bonded acrylic palatal
expansion appliance to control vertical eruptionexpansion appliance to control vertical eruption
of molars has been recommended.of molars has been recommended.

Cases not suitable for face maskCases not suitable for face mask
 Severe skeletal class III malocclusionSevere skeletal class III malocclusion
 Hyperdivergent growth patternHyperdivergent growth pattern
 Minimal overbiteMinimal overbite

Types of face maskTypes of face mask
 Face mask of Delaire:Face mask of Delaire:
consist of forehead cap,&aconsist of forehead cap,&a
chincap connected by squarishchincap connected by squarish
framework with a wire runningframework with a wire running
infront of the mouth used forinfront of the mouth used for
elastic attachment.elastic attachment.
 Petit type of face mask:Petit type of face mask:
Consist of chincup &a foreheadConsist of chincup &a forehead
cap with a single rod connecting incap with a single rod connecting in
the midline from forehead cap tothe midline from forehead cap to
chincup.chincup.

 Suborbital ProtractionSuborbital Protraction
(Grummons)(Grummons)
 This apparatus has been redesignedThis apparatus has been redesigned
to increase the rigidity of the mainto increase the rigidity of the main
frame and make the device easier toframe and make the device easier to
adjust. The zygomatic anchorageadjust. The zygomatic anchorage
areas support the appliance well,areas support the appliance well,
and the reciprocal force of theand the reciprocal force of the
elastics to the teeth is felt at the backelastics to the teeth is felt at the back
of the head.of the head.
 The major disadvantage is theThe major disadvantage is the
esthetic objection to midfacialesthetic objection to midfacial
support.support.

 Protraction Head gear (Hickham):Protraction Head gear (Hickham):
 The appliance does not interfereThe appliance does not interfere
with sleep, is somewhat morewith sleep, is somewhat more
esthetic than other protractionesthetic than other protraction
devices, and has unilateraldevices, and has unilateral
capabilities . Disadvantage is that itcapabilities . Disadvantage is that it
must be carefully adjusted to fitmust be carefully adjusted to fit
comfortably behind the ears.comfortably behind the ears.
 Modification by NandaModification by Nanda

 Tubinger model:Tubinger model:
Modified type of delaire faceModified type of delaire face
mask,consist of a chin cupmask,consist of a chin cup
from which originates 2 rodsfrom which originates 2 rods
that run in the midline &isthat run in the midline &is
shaped to avoid theshaped to avoid the
interference of nose.interference of nose.
Superior ends of the 2 rodsSuperior ends of the 2 rods
house a forehead cap fromhouse a forehead cap from
which elastic encircles thewhich elastic encircles the
head .head .

COMPONENTS OF ORTHOPEDIC FACIALCOMPONENTS OF ORTHOPEDIC FACIAL
MASKMASK
 facial mask: (extraoral anchorage)facial mask: (extraoral anchorage)
chin cup,chin cup,
forehead cap,forehead cap,
metal framemetal frame
 Intraoral appliance: (intraoralIntraoral appliance: (intraoral
anchorage)anchorage)
bonded maxillary expansion splintbonded maxillary expansion splint
banded maxillary expansion splintbanded maxillary expansion splint
 Elastics.Elastics.

 The Facial MaskThe Facial Mask
 Delaire’s approach involves applyingDelaire’s approach involves applying
'traction to the maxillary sutures while'traction to the maxillary sutures while
reciprocally pushing on the mandible andreciprocally pushing on the mandible and
the forehead through the anchoragethe forehead through the anchorage
provided by the facial mask.provided by the facial mask.
 It is consist of chin cup, forehead cap,It is consist of chin cup, forehead cap,
metal framemetal frame

 The Petit facial mask originallyThe Petit facial mask originally
was constructed on a patient-bywas constructed on a patient-by
patient basis, using 0.25* roundpatient basis, using 0.25* round
lengths of stainless steel, tolengths of stainless steel, to
which pads for the forehead andwhich pads for the forehead and
chin were attached.chin were attached.
 This initial approach was notThis initial approach was not
practical on a routine basispractical on a routine basis

 Latter design was relatively simpleLatter design was relatively simple
in that it contained a single midlinein that it contained a single midline
rod connected to a chin pad androd connected to a chin pad and
forehead pad .forehead pad .
 In addition, elastics wereIn addition, elastics were
connected to an adjustableconnected to an adjustable
crossbow.crossbow.

 Pads are made from acrylicPads are made from acrylic
and are lined with a softand are lined with a soft
closed-cell foam that isclosed-cell foam that is
nonabsorbent, easilynonabsorbent, easily
cleaned and replaceable.cleaned and replaceable.
The pads are connected byThe pads are connected by
a midline framework madea midline framework made
from a round, contouredfrom a round, contoured
length of .25‘’ stainlesslength of .25‘’ stainless
steel with acro nuts onsteel with acro nuts on
each end.each end.
 The positions of the padsThe positions of the pads
are adjustable through theare adjustable through the
loosening and tightening ofloosening and tightening of
a set screw.a set screw. www.indiandentalacademy.comwww.indiandentalacademy.com

 The midline framework also can be bent toThe midline framework also can be bent to
conform better to the outline of the face ofconform better to the outline of the face of
the individual patient.the individual patient.
 The centre of the midline framework Is aThe centre of the midline framework Is a
crossbar made from 0,075" stainless steelcrossbar made from 0,075" stainless steel
that is secured to the main framework by athat is secured to the main framework by a
set screw, thus allowing the position of theset screw, thus allowing the position of the
crossbar to be adjusted vertically. Thecrossbar to be adjusted vertically. The
ends of the crossbar are contoured forends of the crossbar are contoured for
patient safety.patient safety.

Bonded maxillary splintBonded maxillary splint
 In mixed dentition patients,In mixed dentition patients,
the splint usually covers thethe splint usually covers the
first ,second deciduousfirst ,second deciduous
molars and the permanentmolars and the permanent
first molars.first molars.
 The hooks for the elasticsThe hooks for the elastics
arise at the anterior aspect ofarise at the anterior aspect of
the appliance in the region ofthe appliance in the region of
the upper first deciduousthe upper first deciduous
molar.molar.

 In deciduous dentition theIn deciduous dentition the
splint can be constructed sosplint can be constructed so
that the upper canine as wellthat the upper canine as well
as the deciduous molars areas the deciduous molars are
included.included.
 Hooks for the elastic areHooks for the elastic are
fabricated adjacent to thefabricated adjacent to the
maxillary deciduous canines.maxillary deciduous canines.

 In late mixed or early permanent dentition IfIn late mixed or early permanent dentition If
permanent second molars are erupted, it ispermanent second molars are erupted, it is
necessary to place an occlusal rest againstnecessary to place an occlusal rest against
these teeth to prevent supra eruption of thesethese teeth to prevent supra eruption of these
teeth during appliance wire.teeth during appliance wire.
 The framework should not be extended toThe framework should not be extended to
encompass the second molars posteriorlyencompass the second molars posteriorly
because of the danger of opening the bite due tobecause of the danger of opening the bite due to
placement of the acrylic on the occlusal surfacesplacement of the acrylic on the occlusal surfaces
of the upper second molars.of the upper second molars.

 Modifications also can be made in the position ofModifications also can be made in the position of
the facial mask hooks, depending on thethe facial mask hooks, depending on the
direction of force desired.direction of force desired.
 If a downward force on the maxilla, is desired,If a downward force on the maxilla, is desired,
the facial mask hooks are placed at varyingthe facial mask hooks are placed at varying
heights within the maxillary vestibule. If a moreheights within the maxillary vestibule. If a more
horizontal pull is desired, the hooks are placedhorizontal pull is desired, the hooks are placed
adjacent to the acrylic near the occlusal surface.adjacent to the acrylic near the occlusal surface.
 The limiting factor regard to the direction of pullThe limiting factor regard to the direction of pull
is the relative positions of the upper and loweris the relative positions of the upper and lower
lip.lip.

 framework of splint is made of a.045"framework of splint is made of a.045"
round stainless steel wire to which anround stainless steel wire to which an
expansion screw has been soldered.expansion screw has been soldered.
 The hooks for elastic and any occlusal restThe hooks for elastic and any occlusal rest
are made from the same size wire.are made from the same size wire.
 The maxillary splint fabricated usingThe maxillary splint fabricated using
methyl methacrylate resin.methyl methacrylate resin.

Banded palatal expansion :Banded palatal expansion :
 Constructed by using bands fittedConstructed by using bands fitted
on the maxillary primary secondon the maxillary primary second
molars &permanent 1molars &permanent 1stst
molars inmolars in
mixed dentition, primary 1mixed dentition, primary 1stst
molar,molar,
primary 2primary 2ndnd
molars in primarymolars in primary
dentition.dentition.
 Molar bands are joined byMolar bands are joined by
soldering a heavy wire to thesoldering a heavy wire to the
palatal plate ,which had a Hyraxpalatal plate ,which had a Hyrax
type screw in the midline.type screw in the midline.

 0.045 “wire is soldered bilaterally to0.045 “wire is soldered bilaterally to
the buccal aspect of molar bandthe buccal aspect of molar band
&extended anteriorly to the canine&extended anteriorly to the canine
area for protraction with elastics.area for protraction with elastics.

 Function :Function :
Haas(1970, 1973)Haas(1970, 1973) has demonstratedhas demonstrated that rapidthat rapid
palatal expansion can produce a slightly forwardpalatal expansion can produce a slightly forward
movement of Point A and a slightly downwardmovement of Point A and a slightly downward
and forward movement of the maxilla.and forward movement of the maxilla.
 The presumable effect of such expansion is toThe presumable effect of such expansion is to
disrupt maxillary sutural system, thus enhancingdisrupt maxillary sutural system, thus enhancing
the effect of the orthopedic facial mask bythe effect of the orthopedic facial mask by
adjustments occur more readily.adjustments occur more readily.

 The bite opening effect of the maxillaryThe bite opening effect of the maxillary
splint also tendency toward extrusion ofsplint also tendency toward extrusion of
posterior teeth, which has been observedposterior teeth, which has been observed
using the banded appliance.using the banded appliance.
 Another advantage of maxillary expansionAnother advantage of maxillary expansion
is the correction of the posterior crossbiteis the correction of the posterior crossbite
that often accompanies a Class IIIthat often accompanies a Class III
malocclusion because of deficientmalocclusion because of deficient
transverse maxillary growth and thetransverse maxillary growth and the
abnormal anteroposterior relationship ofabnormal anteroposterior relationship of
maxilla to mandible.maxilla to mandible.

In addition, a palatal expansion applianceIn addition, a palatal expansion appliance
splints the maxillary dentition duringsplints the maxillary dentition during
protraction and helps transmit force from theprotraction and helps transmit force from the
teeth to the maxilla, thus limiting unwantedteeth to the maxilla, thus limiting unwanted
tooth movement.tooth movement.

Elastic TractionElastic Traction
 Secured to the face by stretching elasticsSecured to the face by stretching elastics
from the hooks on the maxillary splint tofrom the hooks on the maxillary splint to
the crossbow of the facial mask.the crossbow of the facial mask.
 Heavy forces are generated ,usuallyHeavy forces are generated ,usually
through the use of a sequence of elastics.through the use of a sequence of elastics.
 Forces should be increased as the patientForces should be increased as the patient
adjust to the appliance.adjust to the appliance.

Clinical managementClinical management
 ImpressionImpression
 Take an alginate impression of upper forTake an alginate impression of upper for
fabrication of the maxillary splint. Thefabrication of the maxillary splint. The
impressions should be checked for properimpressions should be checked for proper
reproduction of the teeth and associatedreproduction of the teeth and associated
soft tissue.soft tissue.

 Splint FabricationSplint Fabrication
 The wire framework is formed from .The wire framework is formed from .
045“SS that is contoured to the posterior045“SS that is contoured to the posterior
teeth.teeth.
 Hooks facing posteriorly are soldered toHooks facing posteriorly are soldered to
the framework on each side in the regionthe framework on each side in the region
of the canine and first deciduous molar.of the canine and first deciduous molar.
 An expansion screw is placed in theAn expansion screw is placed in the
middle of the palate and soldered in place.middle of the palate and soldered in place.

 Bonding ProcedureBonding Procedure
 The maxillary splint is bonded to the posteriorThe maxillary splint is bonded to the posterior
teeth in the following manner.teeth in the following manner.
 Clean maxillary teeth with a rotating rubber cupClean maxillary teeth with a rotating rubber cup
and non-fluoridated pumice.and non-fluoridated pumice.
 The isolate the dental arch .The isolate the dental arch .
 Etch the teeth with (37 %) solution of phosphoricEtch the teeth with (37 %) solution of phosphoric
acid.acid.
 Only the buccal and lingual surfaces of the teethOnly the buccal and lingual surfaces of the teeth
are etched. The occlusal surfaces are notare etched. The occlusal surfaces are not
etched, to facilitate removal of the appliance.etched, to facilitate removal of the appliance.

 A four-handed approach is advisable whenA four-handed approach is advisable when
bonding the splint.bonding the splint.
 Firm pressure is applied initially to force theFirm pressure is applied initially to force the
excess bonding material out of the splint. Inexcess bonding material out of the splint. In
most cases, pressure can then be released frommost cases, pressure can then be released from
the splint and the clinician can begin the clean-the splint and the clinician can begin the clean-
up process using cotton applicators and aup process using cotton applicators and a
universal scaler.universal scaler.

 The bonding material is not viscous when it isThe bonding material is not viscous when it is
first setting, and it is necessary to use cottonfirst setting, and it is necessary to use cotton
applicators to remove the excess material.applicators to remove the excess material.
 As the gel phase of the setting begins, theAs the gel phase of the setting begins, the
bonding material becomes much thicker and isbonding material becomes much thicker and is
easily removed from the appliance with a scaler.easily removed from the appliance with a scaler.
 Once the bonding agent has set, a bur in aOnce the bonding agent has set, a bur in a
handpiece is needed to remove excess bondinghandpiece is needed to remove excess bonding
material.material.

 Then the splint is check for voids,Then the splint is check for voids,
particularly along the gingival margin. Aparticularly along the gingival margin. A
second application of bonding agent cansecond application of bonding agent can
be used to fill any voids. Failure to fill abe used to fill any voids. Failure to fill a
void can result in decalcification of thevoid can result in decalcification of the
associated teeth during treatment.associated teeth during treatment.

Activation of the SplintActivation of the Splint
 Appliance is activated twice daily (0.25mmperAppliance is activated twice daily (0.25mmper
turn )for 1 week.turn )for 1 week.
 In the majority of Class III individuals in whomIn the majority of Class III individuals in whom
use of an orthopedic facial mask is indicated,use of an orthopedic facial mask is indicated,
some maxillary expansion is beneficial. In such asome maxillary expansion is beneficial. In such a
case, the maxillary splint is expanded until thecase, the maxillary splint is expanded until the
desired transverse change is achieved.desired transverse change is achieved.
 In instances in which no transverse change isIn instances in which no transverse change is
necessary, the maxillary splint is activated oncenecessary, the maxillary splint is activated once
a day for eight days to produce a disruption ina day for eight days to produce a disruption in
the sutural system that facilitates the action ofthe sutural system that facilitates the action of
the facial mask.the facial mask.

Delivery of the Facial MaskDelivery of the Facial Mask
 The appliance is held against the face ofThe appliance is held against the face of
the patient and the positions of thethe patient and the positions of the
forehead and chin pads are adjusted byforehead and chin pads are adjusted by
loosening the set screws . The position ofloosening the set screws . The position of
the crossbar is similarly adjusted in thethe crossbar is similarly adjusted in the
vertical dimension to allow the elastics tovertical dimension to allow the elastics to
pass through the interlabial gap withoutpass through the interlabial gap without
producing discomfort to the patient.producing discomfort to the patient.

 The elastics are connected bilaterally fromThe elastics are connected bilaterally from
the hooks in the canine or first deciduousthe hooks in the canine or first deciduous
molar regions of the maxillary splint to onemolar regions of the maxillary splint to one
of the indentations produced by theof the indentations produced by the
contours of the crossbar . The elasticscontours of the crossbar . The elastics
travel in an inferomedial directiontravel in an inferomedial direction
anteriorly from the hooks on the splint toanteriorly from the hooks on the splint to
the crossbar. Care must be taken that thethe crossbar. Care must be taken that the
elastics do not cause irritation to theelastics do not cause irritation to the
corners of the mouth.corners of the mouth.

 Optimally, the patient is instructed to wear theOptimally, the patient is instructed to wear the
facial mask on a full-time basis except duringfacial mask on a full-time basis except during
meals. Young patients (5 to 9 years old) canmeals. Young patients (5 to 9 years old) can
usually follow this regimen, particularly if theusually follow this regimen, particularly if the
patient is told that the full-time wear will last onlypatient is told that the full-time wear will last only
three to five months.three to five months.
 In older patients, full-time wear may not beIn older patients, full-time wear may not be
possible, in which case the appliance should bepossible, in which case the appliance should be
worn at all times except when the patient is inworn at all times except when the patient is in
school or participating in contact sports.school or participating in contact sports.

 Patients should be instructed to rigorouslyPatients should be instructed to rigorously
maintain a high level of oral hygiene andmaintain a high level of oral hygiene and
to report immediately any indications thatto report immediately any indications that
the bonded splint might be loosening inthe bonded splint might be loosening in
any area.any area.
 The patient should be seen every three orThe patient should be seen every three or
four weeks to check the condition of thefour weeks to check the condition of the
splint and to evaluate hard and soft tissuesplint and to evaluate hard and soft tissue
changes.changes.

Sequential Use of ElasticsSequential Use of Elastics
 At the time of the delivery of the facial mask, theAt the time of the delivery of the facial mask, the
use of bilateral 3/8", 8 oz. elastics for the firstuse of bilateral 3/8", 8 oz. elastics for the first
two weeks is recommended.two weeks is recommended.
 After that time, the force on the mask isAfter that time, the force on the mask is
increased by using I/2‘’, 14oz-elastcs .increased by using I/2‘’, 14oz-elastcs .
 If a patient develops redness or other problemsIf a patient develops redness or other problems
with the soft tissue, the amount of elastic forcewith the soft tissue, the amount of elastic force
can be lessened or the duration of appliancecan be lessened or the duration of appliance
wear can be reduced. Care should be taken towear can be reduced. Care should be taken to
make sure that excess pressure is not applied tomake sure that excess pressure is not applied to
the soft tissue.the soft tissue. www.indiandentalacademy.comwww.indiandentalacademy.com

Discontinuation of the treatmentDiscontinuation of the treatment
 Usually worn until a positive overjet ofUsually worn until a positive overjet of
2.5mm is achieved interincisally.2.5mm is achieved interincisally.
 At this time, part-time or nighttime wear isAt this time, part-time or nighttime wear is
recommended for an additional 3 to-6recommended for an additional 3 to-6
month retention period.month retention period.
 A removable palatal stabilization plate withA removable palatal stabilization plate with
arrow clasps between the 1arrow clasps between the 1stst
&2&2ndnd
deciduousdeciduous
molars is worn full time.molars is worn full time.www.indiandentalacademy.comwww.indiandentalacademy.com

 In cases of profound neuromuscularIn cases of profound neuromuscular
imbalances ,the FR-3 appliance of Frankel canimbalances ,the FR-3 appliance of Frankel can
be worn as an active retainer.be worn as an active retainer.
 During retention, a mandibular retractor or a
Class III activator with a posterior bite block can
be used for vertical control.
 Facial mask should be discontinued immediatelyFacial mask should be discontinued immediately
if the patient complains of any symptoms ofif the patient complains of any symptoms of
temperomandibular Disorders.temperomandibular Disorders.

Anatomy of craniomaxillary areaAnatomy of craniomaxillary area
The maxilla articulates with nine other bones ofThe maxilla articulates with nine other bones of
the craniofacial complex:the craniofacial complex:
frontal, nasal,frontal, nasal,
lacrimal, ethmoid,lacrimal, ethmoid,
palatine, vomer, zygoma,palatine, vomer, zygoma,
inferior nasal concha,inferior nasal concha,
opposite maxilla, and occasionally sphenoid.opposite maxilla, and occasionally sphenoid.
Palatal expansion affects not only thePalatal expansion affects not only the
intermaxillary suture, but all of theseintermaxillary suture, but all of these
circummaxillary articulations.circummaxillary articulations.

 DellingerDellinger (A.J.O-1973)(A.J.O-1973)
 In a preliminary study using two macacaIn a preliminary study using two macaca
monkeys, examined anterior maxillarymonkeys, examined anterior maxillary
displacement following rapid palatal expansiondisplacement following rapid palatal expansion
and the application of a heavy (6 pounds)and the application of a heavy (6 pounds)
anterior force via a spring attached to theanterior force via a spring attached to the
expansion appliance.expansion appliance. He reported that the
maxilla separated from the pterygoid and
repositioned anteriorly with orthopedic forces
significantly over a period of 7 days.significantly over a period of 7 days.
 KambaraKambara ((AJO-1977AJO-1977))
 Used 300 Gm. of intermitent force on six MacacaUsed 300 Gm. of intermitent force on six Macaca
monkeys with five controls and showed that the maxillarymonkeys with five controls and showed that the maxillary
complex can be displaced anteriorly.complex can be displaced anteriorly.

 NandaNanda (AJO- 1978 Aug )(AJO- 1978 Aug )
 Study comprises of metallic implants, vitalStudy comprises of metallic implants, vital
staining, roentgenographic cephalometry, andstaining, roentgenographic cephalometry, and
carefully executed histologic techniques,carefully executed histologic techniques,
 The results show that the midfacial bones canThe results show that the midfacial bones can
be displaced anteriorly by sutural modification.be displaced anteriorly by sutural modification.
The nature of movement was found to be relatedThe nature of movement was found to be related
to the direction of force. The study revealed thatto the direction of force. The study revealed that
with the same line of force, different midfacialwith the same line of force, different midfacial
bones displace in different directions, probablybones displace in different directions, probably
because of the various moments of forcebecause of the various moments of force
generated at the sutures.generated at the sutures.

 Jackson & IshiiJackson & Ishii
 Reported that the maxillary complex ofReported that the maxillary complex of
monkeys exhibited a marked anteriormonkeys exhibited a marked anterior
positioning with a small amount of anteriorpositioning with a small amount of anterior
rotation and the remodeling of bones wasrotation and the remodeling of bones was
produced not only at the sutural areas butproduced not only at the sutural areas but
also on the surfaces of bones.also on the surfaces of bones.

Centre of Resistance of MaxillaCentre of Resistance of Maxilla
 Tanne and Hiroto,Tanne and Hiroto, (J Biomed Eng. 1988)(J Biomed Eng. 1988)
The center of resistance of the maxilla isThe center of resistance of the maxilla is
located between the root tips of the upperlocated between the root tips of the upper
first and second premolars.first and second premolars.
 Staggers et alStaggers et al (J Clin Orthod. 1992)(J Clin Orthod. 1992)
Found it to be at the level of the zygomaticFound it to be at the level of the zygomatic
buttress.buttress.

 Hata et al,Hata et al,
The center of resistance of the maxilla is locatedThe center of resistance of the maxilla is located
5 mm above the nasal floor. They studied the5 mm above the nasal floor. They studied the
effects of changing the level of force applicationeffects of changing the level of force application
on the maxilla in protraction procedureson the maxilla in protraction procedures
 Lee K etal: (AJODO1997)Lee K etal: (AJODO1997)
Found it to be located at the distal contacts ofFound it to be located at the distal contacts of
the maxillary 1the maxillary 1stst
molas one half the distance frommolas one half the distance from
functional occlusal plane to the inferior border offunctional occlusal plane to the inferior border of
the orbit..the orbit..

Variability in clinical responseVariability in clinical response
Amount of forward maxillary movement isAmount of forward maxillary movement is
influenced by a number of factorsinfluenced by a number of factors
 Age of patient,Age of patient,
 Use of anchorage system (with or withoutUse of anchorage system (with or without
an expansion appliance,an expansion appliance,
 The force level,The force level,
 Direction & point of force application,Direction & point of force application,
treatment time.treatment time.

Age of patientAge of patient
 Some studies suggest that face mask/expansionSome studies suggest that face mask/expansion
therapy may be the most effective in the primarytherapy may be the most effective in the primary
&early mixed dentition.&early mixed dentition.
 Other studies also suggest that it is a viableOther studies also suggest that it is a viable
option for older children before the onset ofoption for older children before the onset of
puberty.puberty.
 It appears that the maintenance of an anteriorIt appears that the maintenance of an anterior
occlusion is extremely important to sustain theocclusion is extremely important to sustain the
overbite and overjet correction.overbite and overjet correction.

 CozzaniCozzani (Ajo-1981)(Ajo-1981)
Reported that when the patient is treatedReported that when the patient is treated
at age 4 years, the direction of the growthat age 4 years, the direction of the growth
of the maxilla coincides with the directionof the maxilla coincides with the direction
of the protraction, which results inof the protraction, which results in
increased stability.
 Irie and NakamuraIrie and Nakamura (Ajo-1977)(Ajo-1977)
suggested that the period of Hellman'ssuggested that the period of Hellman's
dental age IIC to IIIA is the optimal time.dental age IIC to IIIA is the optimal time.

 Daniel Merwin, (1997 AjoDo)Daniel Merwin, (1997 AjoDo)
 In a study examined the treatment effects ofIn a study examined the treatment effects of
patients younger than 8 years old (5 to 8 years)patients younger than 8 years old (5 to 8 years)
and patients older than 8 years old (9 to 12and patients older than 8 years old (9 to 12
years).years).
 Results indicated strikingly similar therapeuticResults indicated strikingly similar therapeutic
response between the younger and older ageresponse between the younger and older age
groups. These data suggest that similar skeletalgroups. These data suggest that similar skeletal
response can be obtained when maxillaryresponse can be obtained when maxillary
protraction was started either before age 8 (5 toprotraction was started either before age 8 (5 to
8 years) or after age 8 years (8 to 12 years).8 years) or after age 8 years (8 to 12 years).

 According toAccording to Proffit,Proffit, because early treatmentbecause early treatment
lengthens the treatment period and poses alengthens the treatment period and poses a
danger of relapse, it is better to start at around 6danger of relapse, it is better to start at around 6
to 8 years.to 8 years.
 BaikBaik investigaed 47 subjects who received RPEinvestigaed 47 subjects who received RPE
appliances were divided into three age groups:appliances were divided into three age groups:
below 10 years, 10 to 12 years, and more thanbelow 10 years, 10 to 12 years, and more than
12 years. But, there was no statistically12 years. But, there was no statistically
significant difference among the results of thesignificant difference among the results of the
three groups .three groups .

Design of anchorage SystemDesign of anchorage System
 To protract the maxilla effectively, theTo protract the maxilla effectively, the
force should be applied to the maxilla as aforce should be applied to the maxilla as a
unit. Since the intraoral appliance deliversunit. Since the intraoral appliance delivers
the force to the maxilla from the extraoralthe force to the maxilla from the extraoral
appliances, a properly designed applianceappliances, a properly designed appliance
is critical to the effectiveness of theis critical to the effectiveness of the
protraction device.protraction device.

 Anchorage can be:Anchorage can be:
Palatal arches, lingual archPalatal arches, lingual arch
RME,quad helixRME,quad helix
fixed appliancefixed appliance
Intentional Ankylosed tooth,Intentional Ankylosed tooth,
Endosseous implants.Endosseous implants.
Removable orthodontic appliances.Removable orthodontic appliances.
Expansion had been shown to produce aExpansion had been shown to produce a
forward and downward movement of the maxillaforward and downward movement of the maxilla
by affecting the intermaxillary andby affecting the intermaxillary and
circummaxillary sutures.circummaxillary sutures.

 Some studies shows that need of expansionSome studies shows that need of expansion
before protraction to disarticulate the maxillabefore protraction to disarticulate the maxilla
&initiate cellular response in the circummaxillary&initiate cellular response in the circummaxillary
sutures ,allowing a more positive reaction tosutures ,allowing a more positive reaction to
protraction forces.protraction forces.
 Study byStudy by Baik,Baik, shown significant greater forwardshown significant greater forward
movement of the maxilla when protraction wasmovement of the maxilla when protraction was
initiated in conjunction with RME.initiated in conjunction with RME.
 Greater forward movement of the maxilla wasGreater forward movement of the maxilla was
found when protraction was initiated duringfound when protraction was initiated during
maxillary expansion compared with protractionmaxillary expansion compared with protraction
after expansion.after expansion.

 Baik (ajodo-1995)Baik (ajodo-1995)
The maxilla moved more forward in theThe maxilla moved more forward in the
RPE group, compared with La/Li group.RPE group, compared with La/Li group.
 The palatal plane angle decreased moreThe palatal plane angle decreased more
in the protraction-during-palatal-expansionin the protraction-during-palatal-expansion
group than protraction-after-palatal-group than protraction-after-palatal-
expansion group.expansion group.

Force level,Force level,
 Orthopedic effects require greater forcesOrthopedic effects require greater forces
than orthodontic movements.than orthodontic movements.
 Successful maxillary protraction has beenSuccessful maxillary protraction has been
reported using 300 to 600gm of forces perreported using 300 to 600gm of forces per
side in primary &mixed dentition .side in primary &mixed dentition .
 Tension of the elastics can be estimatedTension of the elastics can be estimated
using a tension stress gauge.using a tension stress gauge.
 Most of the studies recommend for 10 toMost of the studies recommend for 10 to
12 hr/day.12 hr/day.

Hata S, AJ O DO -1987Hata S, AJ O DO -1987
 Several investigators have demonstrated thatSeveral investigators have demonstrated that
dramatic skeletal changes can be obtained indramatic skeletal changes can be obtained in
animals with continuous protraction forces to theanimals with continuous protraction forces to the
maxilla.maxilla.
 An extraoral force of 300 gm or more per side,An extraoral force of 300 gm or more per side,
when applied, can cause significant changes inwhen applied, can cause significant changes in
the circummaxillary sutures and in the maxillarythe circummaxillary sutures and in the maxillary
tuberosity. Tension produced within the suturestuberosity. Tension produced within the sutures
was believe to cause an increase in vascularitywas believe to cause an increase in vascularity
and a concomitant differentiation of the cellularand a concomitant differentiation of the cellular
tissues resulting in increased osteoblastictissues resulting in increased osteoblastic
activity.activity.

Direction, point of applicationDirection, point of application
 The direction of protraction forces is anThe direction of protraction forces is an
important factor in determining patterns ofimportant factor in determining patterns of
repositioning, and sutural modification ofrepositioning, and sutural modification of
the complex is pertinent to its growththe complex is pertinent to its growth
change.change.
 In cases of maxillary deficiency, whetherIn cases of maxillary deficiency, whether
to protract with a clockwise moment on theto protract with a clockwise moment on the
maxilla, a counterclockwise moment, or nomaxilla, a counterclockwise moment, or no
moment.moment.

 If the patient has normal overbite andIf the patient has normal overbite and
normal vertical proportions, protractionnormal vertical proportions, protraction
without any moment is indicated. If thewithout any moment is indicated. If the
patient has an anterior open bite inpatient has an anterior open bite in
addition to the maxillary deficiency, aaddition to the maxillary deficiency, a
clockwise moment should be used. If theclockwise moment should be used. If the
patient has a deep bite, apatient has a deep bite, a
counterclockwise moment should becounterclockwise moment should be
chosen.chosen.

 Hata etal: suggested an effective forwardHata etal: suggested an effective forward
displacement of the maxilla can bedisplacement of the maxilla can be
obtained clinically from a force appliedobtained clinically from a force applied
5mm above the palatal plane.5mm above the palatal plane.
 In several studies a 30 to 45 degreeIn several studies a 30 to 45 degree
forward &downward protraction forceforward &downward protraction force
applied at the canine region produced anapplied at the canine region produced an
acceptable clinical response.acceptable clinical response.

 Nanda, R. J. Dent. Res. 1978.Nanda, R. J. Dent. Res. 1978.
A study on protraction of midfacial bonesA study on protraction of midfacial bones
on primates reported that the point ofon primates reported that the point of
force application significantly influencesforce application significantly influences
the center of rotation of the maxilla inthe center of rotation of the maxilla in
rhesus monkeys.rhesus monkeys.

Alcan Tetal Am J Orthod. 2000
 Recently another design named the Modified
Maxillary Protraction Headgear was introduced.
The investigators.
 Applied the force above the eyes at the level of
the frontal region with a specially designed face
bow to prevent a counterclockwise rotation of
the maxilla. Their results showed that the
appliance is effective to protract the maxilla with
significant clockwise rotation

Ahmet Keles,(AO-2002)
Examined the effect of varying the force
direction on maxillary protraction.
In group 1, applied the force intraorally
from the canine region with a forward and
downward direction at a 30 angle to the
occlusal plane. In group 2, the force was
applied extraorally 20 mm above the
maxillary occlusal plane.

 In group 1 observed that the maxilla advanced
forward with a counter-clockwise rotation.In group 2
observed an anterior translation of maxilla without
rotation.
 The maxillary occlusal plane did not rotate in group
1, in contrast to the clockwise rotation in group 2.
 The maxillary incisors were proclined slightly in
group 1, but in contrast they were retroclined and
extruded in group 2.
 In conclusion, the force application from near the
center of resistance of the maxilla was an effective
method to prevent the unwanted side effects,

The majority of these studies noted a
counterclockwise rotation of the maxilla
with the protraction headgear treatment.
Although this rotation was a benefit in the
treatment of low-angle, deep-bite class III
patients,it is not indicated in class III cases
with high-angle skeletal patterns and
anterior open bites.

 Nanda introduced modified protraction face
bow design in order to deliver the protraction
forces from a higher level and was able to
eliminate the counterclockwise rotation of the
maxilla.
 They studied the effects of changing the level of
force application on the maxilla.
 Applied the force from different levels ranging
from 5 mm under the occlusal plane to 10 mm
above the Frankfort horizontal plane.
 Found that applying the force from a point 5 mm
above the palatal plane and 15 mm above the
occlusal plane resulted in elimination of the
counterclockwise rotation effect on the maxilla.

TREATMENT EFFECTS PRODUCED BYTREATMENT EFFECTS PRODUCED BY
FACIAL MASK THERAPYFACIAL MASK THERAPY
 Correction of CO-CR discrepancy. ThisCorrection of CO-CR discrepancy. This
correction is immediate and usually Iscorrection is immediate and usually Is
observed In pseudo-Class III patients.observed In pseudo-Class III patients.
 Maxillary skeletal protraction. Usually 1-2Maxillary skeletal protraction. Usually 1-2
mm of forward movement of the maxilla ismm of forward movement of the maxilla is
observed.observed.

 Forward movement of the maxillaryForward movement of the maxillary
dentition.dentition.
 Lingual tipping of the lower Incisors. ThisLingual tipping of the lower Incisors. This
tipping often occurs as a pre-existingtipping often occurs as a pre-existing
anterior crossbite is being corrected.anterior crossbite is being corrected.
Redirection of mandibular growth in aRedirection of mandibular growth in a
more vertical direction.more vertical direction.

Treatment Effects
McNamara and Brudon reported that the
treatment effects of the maxillary rotation
included an inferioanterior movement of the
maxilla and maxillary dentition, clockwise
rotation of the mandible, retroclination of
the mandibular incisor, and increase of the
lower facial height.

R. W. Gallagher, (AJODO-1998)
 1. Maxillary protraction with a face mask produced
a significant, forward movement of the maxilla. This
skeletal movement was accomplished by a force
that is below the center of resistance of the maxilla
and directed downward and forward, dropping the
posterior maxilla down more than the anterior.
 2. The distraction forces temporarily rotated the
mandible downward and backward, which
accounted for the greatest improvement in the
profile.
 3. The lower incisors compensated to the rotation
by uprighting, perhaps related with soft tissue
pressures.

 Ikue Yoshida,Ikue Yoshida, etal: AO-1999etal: AO-1999
During treatment, forward movement of the maxillaDuring treatment, forward movement of the maxilla
with counterclockwise rotation, and backward andwith counterclockwise rotation, and backward and
downward movement of the mandible with clockwisedownward movement of the mandible with clockwise
rotation and growth retardation were observed. Therotation and growth retardation were observed. The
forward movement of the maxilla persisted untilforward movement of the maxilla persisted until
growth was complete.growth was complete.
During the post treatment period, the mandibleDuring the post treatment period, the mandible
maintained its improved position but showedmaintained its improved position but showed
excessive growth, which could be a reboundexcessive growth, which could be a rebound
change.change. www.indiandentalacademy.comwww.indiandentalacademy.com

Shiva ShankerShiva Shanker( AJO-DO 1996)( AJO-DO 1996)
 Results showed that 6 months of maxillaryResults showed that 6 months of maxillary
protraction therapy produced a mean Aprotraction therapy produced a mean A
point advancement of 2.4 mm comparedpoint advancement of 2.4 mm compared
with 0.2 mm in the control group.with 0.2 mm in the control group.
 Of this advancement, 75% was found toOf this advancement, 75% was found to
be due to skeletal maxillary advancementbe due to skeletal maxillary advancement
and 25% was attributed to localand 25% was attributed to local
remodeling.remodeling.

 Vertical A point change was a 0.3 mmVertical A point change was a 0.3 mm
downward movement in the treatmentdownward movement in the treatment
group compared with 1.0 mm downwardgroup compared with 1.0 mm downward
movement in the control group. There foremovement in the control group. There fore
treatment appears to inhibit the normaltreatment appears to inhibit the normal
downward movement of A point.downward movement of A point.
 Ishii et al.Ishii et al.
Reported an increase in maxillary lengthReported an increase in maxillary length
of 2.7 mm in noncleft patients protractedof 2.7 mm in noncleft patients protracted
for 16 months with no maxillary expansion.for 16 months with no maxillary expansion.

 MermigosMermigos (AJODO 1990),(AJODO 1990), (cephalometric study)(cephalometric study)
 Compared pretreatment and posttreatmentCompared pretreatment and posttreatment
cephalograms revealed a significant increase incephalograms revealed a significant increase in
the SNA angle that indicated the maxilla wasthe SNA angle that indicated the maxilla was
positioned farther forward after reverse headgearpositioned farther forward after reverse headgear
therapy. Both the maxillary and the mandibulartherapy. Both the maxillary and the mandibular
effective lengths increased significantly fromeffective lengths increased significantly from
pretreatment to posttreatment, as did anterior andpretreatment to posttreatment, as did anterior and
posterior total face height.posterior total face height.
 There was no significant change in theThere was no significant change in the
anteroposterior position of the mandible, althoughanteroposterior position of the mandible, although
there was a tendency for the mandibular planethere was a tendency for the mandibular plane
angle and the gonial angle to decrease.angle and the gonial angle to decrease.

 Kazuo TanneKazuo Tanne, (in a finite element, (in a finite element
&cephalometric analyses)&cephalometric analyses)
 Tensile stresses were produced in the maxillaryTensile stresses were produced in the maxillary
and zygomatic bones in an anterior directionand zygomatic bones in an anterior direction
with corresponding compressive stresses in awith corresponding compressive stresses in a
perpendicular direction. In the sutural systems,perpendicular direction. In the sutural systems,
compressive stresses were induced by counter-compressive stresses were induced by counter-
clockwise rotation of the complex.clockwise rotation of the complex.
 Cephalometric investigation demonstrated thatCephalometric investigation demonstrated that
significant improvement of the maxillo-significant improvement of the maxillo-
mandibular relationship was obtained bymandibular relationship was obtained by
maxillary protraction, however, maxillary growthmaxillary protraction, however, maxillary growth
and repositioning were not as great whenand repositioning were not as great when
compared to mean growth in the control group.compared to mean growth in the control group.www.indiandentalacademy.comwww.indiandentalacademy.com

 Valmy Pangrazio-Kulbersh,(AJO 1998 ))
 The protraction group showed significant
increases in ANB angle, Wits, A perpendicular to
nasion and in sella to A point.
 Anterior molar movement, without changes in
posterior nasal spine or upper incisor to SN, was
evident with favorable change in the facial profile
was noted.
 The control group did not demonstrate any
significant changes in the position of the maxillary
complex as a result of expansion mechanics.

Hu¨ lya Kilic¸ etal (AJO 1998)
(Cephalometric study)
 Found maxilla displaced anteriorly, whereas the
mandible rotated posteriorly;
 Maxillary incisors moved in the anterior direction,
whereas the mandibular incisors moved
posteriorly
 The mandibular plane angle and anterior lower
and total face heights increased
 these changes were reflected in the profile,
whereby the skeletal profile convexity increased
and soft tissue facial angle and facial convexity
decreased; and the Class III concave profile
became more balanced, with the upper lip area
becoming more marked.www.indiandentalacademy.comwww.indiandentalacademy.com

Nartallo-Turley (AO-1998):Nartallo-Turley (AO-1998):
(In a cephalometric Study)(In a cephalometric Study)
 Statistically significant ant movement of maxillaStatistically significant ant movement of maxilla
occurred withoccurred with SNA ,maxillary depth, ANBSNA ,maxillary depth, ANB
&anterior movement of A point &ANS.&anterior movement of A point &ANS.
 Maxilla rotated counterclockwise with PNS movingMaxilla rotated counterclockwise with PNS moving
down more than ANS .down more than ANS .
 Mandible rotated clockwise with mildMandible rotated clockwise with mild ↓ in SNB.↓ in SNB.
 Maxillary molars moved forwards as did the incisors.Maxillary molars moved forwards as did the incisors.
 Soft tissue changes included the nose &upper lipSoft tissue changes included the nose &upper lip
moving forward &menton moving downward.moving forward &menton moving downward.

Chong etal (AO-1996)Chong etal (AO-1996)
 Found significant improvement in the maxillomandibularFound significant improvement in the maxillomandibular
relationship and overjet .relationship and overjet .
 Major treatment effect was a downward and backwardMajor treatment effect was a downward and backward
movement of the mandible and retroclination of themovement of the mandible and retroclination of the
mandibular incisors. However, any skeletal andmandibular incisors. However, any skeletal and
dentoalveolar advancement of the maxilla contributed todentoalveolar advancement of the maxilla contributed to
the clinically significant improvement.the clinically significant improvement.
 No differences were observed between the patients and theNo differences were observed between the patients and the
controls during the posttreatment follow-up. Despite somecontrols during the posttreatment follow-up. Despite some
relapse, the patients demonstrated a net improvement inrelapse, the patients demonstrated a net improvement in
maxillomandibular relationship and overjet at the end ofmaxillomandibular relationship and overjet at the end of
follow-up relative to the controls.follow-up relative to the controls.

Baccetii etal:Baccetii etal:
(morphometric study)(morphometric study)
 Found significant changes by forwardFound significant changes by forward
displacement of the maxillary complexdisplacement of the maxillary complex
from the ptrygoid region & antfrom the ptrygoid region & ant
morphogenetic rotation of the mandiblemorphogenetic rotation of the mandible
due to upward &forward growth of thedue to upward &forward growth of the
mandibular condyle.mandibular condyle.

Effect on muscleEffect on muscle
Peter W Ngan: (Angle-1996)Peter W Ngan: (Angle-1996)
 Studied masticatory muscle pain &EMGStudied masticatory muscle pain &EMG
activity in patients treated with mphg.activity in patients treated with mphg.
 Result showed no significant differencesResult showed no significant differences
for masticatory muscle activity beforefor masticatory muscle activity before
during &after treatment.during &after treatment.
 None of the patients experiencedNone of the patients experienced
masticatory muscle pain after 1 month.masticatory muscle pain after 1 month.

Soft tissueSoft tissue
 Peter Ngan (Ajodo-1996Peter Ngan (Ajodo-1996 ))
 The results showed significant improvements inThe results showed significant improvements in
dentofacial profile after 6 months of maxillarydentofacial profile after 6 months of maxillary
protraction. The skeletal and soft tissue facialprotraction. The skeletal and soft tissue facial
profiles were straightened and the posture of theprofiles were straightened and the posture of the
lips was improved.lips was improved.
 Significant correlations were found betweenSignificant correlations were found between
changes in the sagittal relationships of skeletalchanges in the sagittal relationships of skeletal
and soft tissue profiles in both the maxilla andand soft tissue profiles in both the maxilla and
the mandible .the mandible .


 The forward movement of the maxilla wasThe forward movement of the maxilla was
accompanied by a corresponding forwardaccompanied by a corresponding forward
movement of the soft tissue profile at 50%movement of the soft tissue profile at 50%
to 79% of the hard tissue.to 79% of the hard tissue.
 In the mandible, the downward andIn the mandible, the downward and
backward movements of the soft tissuesbackward movements of the soft tissues
were equivalent to 71% to 81% of thewere equivalent to 71% to 81% of the
corresponding hard tissuescorresponding hard tissues

Chaconas (AJODO-1985)Chaconas (AJODO-1985)
(photoelastic study)(photoelastic study)
 Photoelasticity offers a method of stressPhotoelasticity offers a method of stress
analysis that is suitable for visualizing theanalysis that is suitable for visualizing the
effects of forces on complex structures.effects of forces on complex structures.
 The protraction forces placed on theseThe protraction forces placed on these
appliances were parallel to the occlusalappliances were parallel to the occlusal
plane, a downward vector 20° to theplane, a downward vector 20° to the
occlusal plane, and a combination ofocclusal plane, and a combination of
these two vectors. The resulting stressthese two vectors. The resulting stress
patterns were observed.patterns were observed.

 Both a parallel traction and a 20°Both a parallel traction and a 20°
downward pull to the occlusal planedownward pull to the occlusal plane
caused a constriction of the anterior portioncaused a constriction of the anterior portion
of the maxilla. The parallel traction causedof the maxilla. The parallel traction caused
a counterclockwise (opening) rotation ofa counterclockwise (opening) rotation of
the molar tooth and palatal plane. A 20°the molar tooth and palatal plane. A 20°
downward force to the occlusal planedownward force to the occlusal plane
decreased this effect.decreased this effect.

Posttreatment ChangesPosttreatment Changes
 Shiva Shanker (AJO-DO 1996)Shiva Shanker (AJO-DO 1996)
A point moved downward and forward by similarA point moved downward and forward by similar
amounts in both the control and treatmentamounts in both the control and treatment
groups, indicating that maxillary growth in thegroups, indicating that maxillary growth in the
treated group reverted to the control level.treated group reverted to the control level.
 More significantly, the results showed that thereMore significantly, the results showed that there
was no relapse in the achieved forwardwas no relapse in the achieved forward
movement of the maxilla, even without the usemovement of the maxilla, even without the use
of any retention devices.of any retention devices.

 Jackson and colleagues:Jackson and colleagues:
Found relapse following the termination ofFound relapse following the termination of
active force& found the degree of relapseactive force& found the degree of relapse
to be directly proportional to the length ofto be directly proportional to the length of
stabilization.stabilization.

R. W. Gallagher, (AJODO-1998)
1.The maxilla showed a relative relapse by
not displacing forward as much as normal.
The anterior rotation caused by treatment
was negated.
2. The mandible followed to a normal
downward and forward growth pattern.
3. The lower incisors were flared partly
because of the use of fixed appliances.

 IshiiIshii found that the relapse of facialfound that the relapse of facial
bones was very slight and the modality ofbones was very slight and the modality of
relapse was divided into two phases— therelapse was divided into two phases— the
posterior rotation of the maxillary complexposterior rotation of the maxillary complex
taking place 1 month after removal of thetaking place 1 month after removal of the
applied forces and the dental changesapplied forces and the dental changes
following the protraction period.following the protraction period.

Effect on the AirwayEffect on the Airway
Shigetoshi Hiyama et al (AO-2001)Shigetoshi Hiyama et al (AO-2001)
Revealed that maxillary growth had a significantRevealed that maxillary growth had a significant
positive effect on the superior upper-airwaypositive effect on the superior upper-airway
dimension.dimension.
 Possible explanations include the increase in thePossible explanations include the increase in the
volume of the oral cavity possibly induced byvolume of the oral cavity possibly induced by
increased maxillary forward growth could bringincreased maxillary forward growth could bring
the tongue to a more anterior position. Thisthe tongue to a more anterior position. This
change in tongue posture could induce the softchange in tongue posture could induce the soft
palate to a more anterior position, which mightpalate to a more anterior position, which might
result in an increase in the superior upper-airwayresult in an increase in the superior upper-airway
dimension.dimension.

 Clockwise rotation of the mandible mightClockwise rotation of the mandible might
also influence the tongue posture. Thealso influence the tongue posture. The
orthopedic force applied by the MPA mightorthopedic force applied by the MPA might
induce an anterior displacement of PNS,induce an anterior displacement of PNS,
which could result in a forward movementwhich could result in a forward movement
of the soft palate and an increase in theof the soft palate and an increase in the
superior upper-airway dimension.superior upper-airway dimension.

conclusionconclusion
 Maxillary protraction force producesMaxillary protraction force produces
anterior repositioning and subsequentanterior repositioning and subsequent
growth of the maxillary complex ingrowth of the maxillary complex in
biomechanical and morphologicalbiomechanical and morphological
aspects. The direction and applicationaspects. The direction and application
point of the force are important forpoint of the force are important for
inducing more efficient maxillaryinducing more efficient maxillary
growth and displacement in thegrowth and displacement in the
anterior direction.anterior direction.

 Protraction HeadgearProtraction Headgear
 The appliance does notThe appliance does not
interfere with sleep, isinterfere with sleep, is
somewhat more estheticsomewhat more esthetic
than other protractionthan other protraction
devices, and hasdevices, and has
unilateral capabilities .unilateral capabilities .
The chief disadvantage isThe chief disadvantage is
that it must be carefullythat it must be carefully
adjusted to fit comfortablyadjusted to fit comfortably
behind the ears.behind the ears.

 Macaca monkeys. Nanda5 has shown that the forward
 movement and the anterior displacement of the maxilla
are
 because of the remodeling of the circummaxillary
sutures,
 in particular the zygomaticomaxillary,
zygomaticotemporal,
 and transverse palatine sutures, and reported that the
type
 of displacement was related to the direction of force.

Bjo¨rk11 reported that appositional growth
in the maxillary
tuberosity area related to the pyramidal
process of the palate
and the pterygoid process of the sphenoid
is important in
growth of the maxilla.

 Palatal expansion produces a forward and downward
 movement of the maxilla by affecting the intermaxillary
 and circummaxillary sutures, and the disruption of these
 sutures may allow for a more positive reaction to the protraction
 forces.
 Kambaram suggested that reactions in the
 suture when protraction force are applied to the maxilla
 might occur as a result of an opening of the suture, stretching
 of sutural connective tissue fibers, new bone deposition,
 and homeostasis, which had maintained the sutural width.
 10–14 years, and showed minimal statistical differences between
 the three age groups when comparing angular and

 One of the most important factors in considering
facial
 mask treatment is the optimization of treatment
timing.
 Irie
 and Nakamura15 suggested that the period of
Hellman’s
 dental age IIC and IIIA is the optimal time.
Kambara14 and Jackson et al17 reported that
maxillary protraction
 should be carried out during the growing stage.

 Petit modified the Delaire mask.
In essence, his facialmask consisted of a forehead pad
and a chin pad that were connected with a heavy steel
rod. Intraorally, a bonded rapid palatal expansion
appliance was used. Forward traction of the maxilla
was accomplished by rubber bands. The treatment
results produced by this appliance were the anterior
movement of the maxilla and downward and
backward rotation of the mandible.

Treatment ChangesTreatment Changes
 The following conclusions were reached: (1)The following conclusions were reached: (1)
protraction forces applied 10 mm above theprotraction forces applied 10 mm above the
Frankfort horizontal plane produced a posteriorFrankfort horizontal plane produced a posterior
rotation of the maxilla with a forward movementrotation of the maxilla with a forward movement
of nasion; (2) protraction forces applied 5 mmof nasion; (2) protraction forces applied 5 mm
above the palatal plane produced a combinationabove the palatal plane produced a combination
of parallel forward movement and a very slightof parallel forward movement and a very slight
anterior rotation; (3) protraction forces applied atanterior rotation; (3) protraction forces applied at
thelevel of the maxillary arch produced anthelevel of the maxillary arch produced an
anterior rotation and forward movement of theanterior rotation and forward movement of the
maxilla; and (4) all three protraction forcesmaxilla; and (4) all three protraction forces
caused the constriction of the anterior part of thecaused the constriction of the anterior part of the
palate.palate.

 a separate .040”ss wire is bent to crossa separate .040”ss wire is bent to cross
the occlusion & ends with a hook forthe occlusion & ends with a hook for
protraction.protraction.
 Acrylic is added on all the occlusalAcrylic is added on all the occlusal
surfaces of the primary molars &surfaces of the primary molars &
permanent molars .permanent molars .

 orthodontic treatment alone is not alwaysorthodontic treatment alone is not always
sufficient for patients who need maxillarysufficient for patients who need maxillary
protraction therapy. The chances of successprotraction therapy. The chances of success
depend on four areas:depend on four areas:
 1. The relationship of the maxilla to the1. The relationship of the maxilla to the
mandible.mandible.
 2. The relationship of the jaws to the cranium.2. The relationship of the jaws to the cranium.
 3. The vertical dimension.3. The vertical dimension.
 4. The age of the patient.4. The age of the patient.

Biomechanical considerationsBiomechanical considerations
 Direction of force:Direction of force:
 Amount of force:Amount of force:
 Duration of force:Duration of force:
 Length of Treatment timeLength of Treatment time
 Treatment time varies from 3 to 16 monthsTreatment time varies from 3 to 16 months

Kyung-Suk Cha, (Angle-73-2003)
 In a cephalometric study evaluated
skeletal and dentoalveolar changes
produced by rapid maxillary expansion
and facial mask therapy in 85 subjects
exhibiting a Class III malocclusion with a
retruded maxillato determine the
relationship between the effect of maxillary
protraction and skeletal age.

 Findings showed:
 (1) There was no difference in the effects of maxillary
advancement after maxillary protraction between the
prepubertal growth peak and the pubertal growth peak
group, but there was a decrease in maxillary skeletal
advancement, increased dentoalveolar effect in the
postpubertal growth peak group,
 (2)The posteroinferior rotation of mandible, the increase
of lower facial height, and the eruption of maxillary
molars showed no correlation with skeletal age.

 The protraction forces that were applied to this applianceThe protraction forces that were applied to this appliance
were parallel to the occlusal plane at the followingwere parallel to the occlusal plane at the following
locations: (1) the height of the maxillary arch, (2) 5 mmlocations: (1) the height of the maxillary arch, (2) 5 mm
above the palatal plane, and (3) 10 mm above theabove the palatal plane, and (3) 10 mm above the
Frankfort horizontal plane. The results indicated that (1)Frankfort horizontal plane. The results indicated that (1)
protraction forces at the level of the maxillary archprotraction forces at the level of the maxillary arch
produced an anterior rotation and forward movement ofproduced an anterior rotation and forward movement of
the maxilla, (2) protraction forces 10 mm above thethe maxilla, (2) protraction forces 10 mm above the
Frankfort horizontal plane produced a posterior rotationFrankfort horizontal plane produced a posterior rotation
of the maxilla with a forward movement of nasion, andof the maxilla with a forward movement of nasion, and
(3) protraction forces 5 mm above the palatal plane(3) protraction forces 5 mm above the palatal plane
produced a combination of parallel forward movementproduced a combination of parallel forward movement
and a very slight anterior rotation of the maxilla.and a very slight anterior rotation of the maxilla.

 Hata, etal 1987Hata, etal 1987
 This study was conducted to evaluate the effectiveness of maxillaryThis study was conducted to evaluate the effectiveness of maxillary
protraction systems. strain gauge transducer systems were used inprotraction systems. strain gauge transducer systems were used in
the analysis of strain distribution and displacement of the humanthe analysis of strain distribution and displacement of the human
skull. The following conclusions were reached: (1) protraction forcesskull. The following conclusions were reached: (1) protraction forces
applied 10 mm above the Frankfort horizontal plane produced aapplied 10 mm above the Frankfort horizontal plane produced a
posterior rotation of the maxilla with a forward movement of nasion;posterior rotation of the maxilla with a forward movement of nasion;
(2) protraction forces applied 5 mm above the palatal plane(2) protraction forces applied 5 mm above the palatal plane
produced a combination of parallel forward movement and a veryproduced a combination of parallel forward movement and a very
slight anterior rotation; (3) protraction forces applied at thelevel ofslight anterior rotation; (3) protraction forces applied at thelevel of
the maxillary arch produced an anterior rotation and forwardthe maxillary arch produced an anterior rotation and forward
movement of the maxilla; and (4) all three protraction forces causedmovement of the maxilla; and (4) all three protraction forces caused
the constriction of the anterior part of the palate.the constriction of the anterior part of the palate.

 Sema Yuksel(Ejo-2001) in aSema Yuksel(Ejo-2001) in a
cephalometric study of 2 diff age groupcephalometric study of 2 diff age group
without expansion appliance foundwithout expansion appliance found
significant displacement of maxilla &significant displacement of maxilla &
increase in overjet.increase in overjet.
 Sung &baik found no significantSung &baik found no significant
differences in treatment effectsdifferences in treatment effects
irrespective to age group.irrespective to age group.

Maxillary protraction in orthodontics

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