Class 2 malocclusion

•Introduction
•Classification
•Diagnosis
•Treatment
•Conclusion

 Class II malocclusion is a commonly observed
clinical problem
 Because class II malocclusion is recognized easily
by health professionals as well as by patients ,the
correction of class II may constitute nearly half of the
treatment protocols
 Class II malocclusion essentially defines the saggital
relation between the upper and lower first
permanent molars as propounded by Edward H.
Angle in 1899

AMERICAN EPIDEMIOLOGIC STUDIES
 20%  Class II
 Age : Decrease with age.
25-30% of the mixed dentition
20-25% of early permanent dentition
15-25% of the adult population
 Twice as frequent in whites than blacks
 Native American  5% - 10%
 INTERNATIONAL EPIDEMIOLOGIC STUDIES
 North America, Europe, and North Africa  20%
 Latin America, Middle East and Asia  10% - 15%
 The black African population ↓ 1-10%

ANGLE CLASSIFICATION
 Angle based his classification of malocclusion on
the normal mesiodistal relations of the canines
and of the mesiobuccal cusps of the upper first
molars in relation to the mandibular first molars
 Class II. all the lower teeth occluding distally to
the width of the one bicuspid tooth

 Class II Division 1….. Characterized by more or less
narrowing of the upper arch and lengthened and protruding
upper incisors,… accompanied by abnormal function of the
lip and some form of nasal obstruction and mouth breathing.
 Class II, Division 1 Subdivision…where one of the lateral
halves only is in distal occlusion The relation of the other
lateral half of the lower arch being normal…

 Class II Division 2….is characterized by less
narrowing of the upper arch, lingual inclination of
the upper incisors, and more or less bunching of
these teeth, and is associated with normal nasal
and lip function….
 Class II Division 2 Subdivision…… is confined
only to one side of the mandibular arch, the other
being normal.

MOYERS CLASSIFICATION
AJO 1980; 78: 477-494
Horizontal Vertical
1,2,3,4,5,
SCREENING
DETAILING
DEFINING
TYPING
Basic morphologic
analysis
Class II
analysis
A,B,C,D,E,F

 Type A
 Type B
 Type C
 Type D
 Type E
 Type F
HORIZONTAL TYPES
Normal skeletal, Dental Class II
Syndromal types of class II
Mild skeletal features

TYPE-A (Dental class2)
 Normal skeletal
profile
 Mand dentition
placed normally to
its base
 Max dentition is
protracted
resulting in class2
molar relation
 Increased over-jet
and over-bite

TYPE-B (Max excess)
Mid-face prominence
1° contribution by
maxillary prognathism
Normal mandible

TYPE-C
Retrognathic max and
mandible
Smaller facial dimension
Dental protrusion
More in females

TYPE-D
Smaller than normal
mandible
Normal maxilla
Max dental protrusion

TYPE-E
Max prognathism
and dental
protrusion
Mand dental
protrusion
Characteristic Class
II bimaxillary
protrusion

TYPE-F
It is a large heterogeneous group with
mild skeletal class2 tendencies
It is a milder form of types B,C,D,E.

VERTICAL TYPES
 The five vertical types are not as clearly
differentiated as the four syndromal horizontal
types

TYPE-1 (Steep mandibular plane or high angle case)
 Greater anterior face
height
Mand plane and occlusal
plane are steeper than
normal
 Palate tipped down
ACB tipped up
Typically called “high
angle case” or “long face
syndrome’

TYPE-2 “ Square face”
 MP,PP,OP and ACB
are more horizontal
often converging
 Small gonial angle
 Incisors are more
vetical and a skeletal
deep bite is possible

TYPE-3
 Anteriorly tipped up
palatal plane
 ↓ face height
 Open bite tendency
 If accompanied by a
high MP angle
skeletal open bite is
inevitable

TYPE-4
 PP,MP,OP all are
tipped down leaving
lip line high
 Associated with
Type B (max
excess)

TYPE-5
 PP tipped down
anteriorly with
normal MP,OP
 Tendency for a
skeletal deep bite

DENTAL CLASS-II
Maxillary dental
Protrusion
Mesial drift of upper 1st
molars

MAXILLARY DENTAL PROTRUSION
• Facial convexity
•Dentialveolar problem limited to the maxillary dentition
•Normal mandible and mandibular dentition A-P
•Only affects the lips
•Excessive overjet
•The only departure from normal ceph values are the max
incisors which are protrusive irt NA, SN, FH.

MESIAL DRIFT OF THE 1ST
PERMANENT
MOLARS
•Congenital absence or premature loss of primary
teeth
•May be unilateral or bilateral
•No incisor protrusion
•Normal overjet with crowding in the maxillary arch
caused by loss of arch perimeter.

A skeletal Class II - fault with the maxilla

A-P MAXILLARY EXCESS
•Also referred to as mid face protrusion
•Facial skeletal convexity with a normal mandible
•Protrusion of the entire midface including the nose and infraorbital
areas and upper lip
•Ceph features: ↑ ANB angle
• ↑ WITS appraisal
• ↑ SNA angle
•Dental compensation in the form of mandibular dental protrusion and
maxillary constriction
•Overerruption of lower incisors with deep bite
•Lower lip position

VERTICAL MAXILLARY EXCESS
POSTERIOR VME
•Max post teeth in infra occ
when compared to func occ
plane
•Anterior open bite
•Normal vertical display of
incisors
OVERALL VME
No anterior open bite
↑ vertical display of incisors
Gummy smile

GENERAL FEATURES OF VME
Normal sized mandible in retro position
Narrow nose with a prominent dorsum and narrow alar bases
Increased lower anterior face height with normal or obtuse naso labial
angle
Lip incompetence
Relative chin retrusion and relative maxillary incisor protrusion
Distinguishing features cephalometrically are in the vertical plane
affecting : lower anterior face height
MP angle
vertical positioning of maxillary teeth
angle of inclination

A skeletal Class II - fault with the mandible

Etiology of class II malocclusion
 Inherited
 Intra uterine molding
 Trauma to the mandible (forceps)
 Childhood fractures of the jaws
 Muscle dysfunction 2° to habits

1. Accomplishment of growth increments and the
direction or vector of growth ( horizontal Graber et al
1967)
2. Assesment of the magnitude of growth change
(Woodside1969- 50% exhibit growth spurt in mixed
dentition
3. Inclination and position of the upper and lower incisors
4. Radiographic cephalometrics
1. Etiology
2. Therapeutic possibilities

CEPHALOMETRIC
DIAGNOSIS
 Facial skeleton
 Jaw bases
 Dentoalveolar

SADDLE ANGLE (N-S-Ar)
↑ saddle angle – posterior
condyle postn and a posteriorly
positioned mandible wrt maxilla
and CB
Compensation may be in the
articular angle (angulation) or
ramal length

ARTICULAR ANGLE (S-Ar-Go)
↑ Ar angle – retrognathic
mandible
Affected by
orthodontic/orthopedic therapy
↓ with anterior postn of mand
Closing of bite
Mesial migration of post
segment

GONIAL ANGLE (Ar-Go- Me)
Form of mandible and growth
direction
↓ horizontal growth
↑ vertical growth

 A-P face height:  Cranial base length

Basal Plane AngleAngle of Inclination
ASSESSMENT OF JAW ROTATIONS

Mutual relationship of the rotation jaw
bases( Lavergne and Gasson)

CEPHALOMETRIC DIAGNOSIS
Linear measurement of the jaw bases
Schwartz (1958)
 N-Se: Man Base 20:21
 Ascending ramus: Man Base 5:7
 Max Base: Man Base 2:3

CEPHALOMETRIC DIAGNOSIS
Morphology of the mandible
 Orthognathic
 Retrognathic
 Prognathic

Analysis of dentoalveolar relationships

FUNCTIONAL ANALYSIS
Determination of postural rest position of the
mandible and interposed freeway space
TMJ function
Functional status of the lips, tongue and cheeks

EVALUATION OF THE PATH OF CLOSURE OF
MANDIBLE
Hinge
(Rotary)
Translatory
(Sliding)
Sliding may be caused by neuromuscular abnormalities, disturbances in
dental interrelationships or compensation of skeletal discrepancies

MANDIBLE - Sagittal plane
No functional disturbance
Path of closure is straight up and forward with a hinge movement
of the condyle in the fossa
True Class II malocclusion

Functional disturbance is present
Both rotary and translatory up and
backward shift
Common in cases of ↑ overbite

Path of closure is upward
and forward form point of
initial contact
The malocclusion is more
severe than it appears with
the teeth in occlusion

MANDIBLE - Vertical plane
Infra occ of post segments
Large freeway space
Lip relationship to
anteriors is good
Normal post segment
Small freeway space
Gummy smile, poor lip
line

Coinciding midlines at rest
Lateral slide into cross bites
Midline shift at rest and occ
Usually a skeletal discrepancy
MANDIBLE - Transverse plane

Wyatt, explained, "distal pressure exerted on the mandible and
ultimately on the condyle induces a TMJ disorder (TMD). When the
mandible is forced posteriorly, distal pressure is exerted on the
condyles; the disks above them may be "popped" (protracted)
anteriorly and medially. The condyles are pressed against the vascular,
innervated retrodiscal tissue causing pain.“
Witzig supported the notion of Farrar and McCarty and further added
that patients with Class II, Division 2 deep bite malocclusions, or
patients with retroclined and overretracted maxillary incisors, as a
result of orthodontics with premolar extractions, have a high incidence
of TMD.
TMJ FUNCTION
Wyatt WE. Preventing adverse effects on the temporomandibular joint through
orthodontic treatment. AM J ORTHOD DENTOFAC ORTHOP 1987;91:493-9.

Headgear and Class II
elastics
Grummons alleged that orthodontic mechanotherapies such as
Class II and III elastics, mandibular headgears, facial masks, chin
cups, and balancing side occlusal interferences, can cause TMD.
Finally, Solberg and Seligman, Thompson and Ricketts
expressed similar viewpoints.
Thompson JR. Abnormal function of the temporomandibular joint and related
musculature: orthodontic implications. Part I. Angle Orthod 1986;56:143-63.

Giannelly A A. Orthodontics, condylar position and temporomandibular joint status. Am J
Orthod Dentofacial Orthop 1989; 95: 521–523.
Reynders R M. Orthodontics and temporomandibular disorders: a review of the literature
(1966-1988). Am J Orthod Dentofacial Orthop 1990; 97: 463–471.
The correlations that have been reported between TMD and the
various malocclusion types are low and unlikely to be of direct
clinical significance (even if statistically significant). More
importantly, correlation alone does not imply cause, yet the fact that
such correlations exist appears to form the basis of statements such
as 'Malocclusion is one of the most common causes of
temperomandibular disorders.

TREATMENT OF
CLASS II
MALOCCLUSIONS

EXTRACTION VS.
EXTRACTION VS.
NON EXTACTION
NON EXTACTION
GROWTH
GROWTH
MODULATION
MODULATION DISTRACTION
DISTRACTION
OSTEOGENESIS
OSTEOGENESIS
FIXED
FIXED
FUNCTIONAL
FUNCTIONAL
APPLIANCES
APPLIANCES
CLASS II
CLASS IIELASTICS
ELASTICS
ORTHOPEDIC
ORTHOPEDICFORCES
FORCES
ORTHOGNATHIC
ORTHOGNATHICSURGERY
SURGERY
CAMOUFLAGE
CAMOUFLAGE

Treatment of class II
Primary dentition(3-6yrs)
Pre-adolescents
Early (7-9yrs)
Late (10-11yrs)
Adolescents(12-15yrs)
Adults more than 16yrs

Pre school children (primary
dentition)
Distal step Mesial stepFlush terminal
Mandibular deficiency can be recognized by age 3

 Growth modification can be used to correct
distal step easily
 As growth continues the discrepancy tends to
recur as quickly as it was corrected.( both AP
and Vertical skeletal discrepancy)
 Except in most severe case it is unwise to begin
treatment

Class II Problems in
Pre-Adolescents(7-
11yrs)

Therapeutic methods
 Objectives of mixed dentition treatment for
class II malocclusion
I. Elimination of abnormal perioral muscle
function
II. Anterior positioning of the mandible by
elimination of functionally induced retrusion
and concomitant growth stimulation
III. Growth inhibition of the maxilla

Elimination of abnormal
peri oral muscle function
 Screening therapy
 Does not work in morphogenetic deformities
Vestibular screen
Lower lip shield
Tongue crib

FUNCTIONAL APPLIANCES
 The term "functional appliance" refers to a variety of
removable appliances designed to alter the
arrangement of various muscle groups that influence
the function and position of the mandible in order to
transmit forces to the dentition and the basal bone.
 Muscular forces are generated by altering the
mandibular position sagittally and vertically, resulting
in orthodontic and orthopedic changes

Effects of functional appliance therapy as influencing Class II correction
Acceleration of mandibular growth by
condylar modification
Headgear like effect to the maxilla
and maxillary dentition
Speculated downward and forward
remodeling of the glenoid fossa
(Woodside 1987)
Dental changes include upper incisor changes caused by incorporated
labial bows or springs
Labial tipping of lower incisors

Differential posterior erruption causing correction of the Class II
with clockwise rotation of the occ plane
This however is only advantageous if the vertical ramal growth
compensates otherwise worsening of facial appearance may occur

Maxillary excess
( A-P and Vertical)

 Excessive growth of the maxilla in children with
class II malocclusion often has a vertical as well as
an anteroposterior component (downward and
forward growth)
The effect is to prevent mandibular growth from
being expressed anteriorly
 The goal of the treatment is to restrict growth of the
maxilla while the mandible grows into a more
prominent and normal relationship with it

Development of head gear
 Extra oral force in the form of head gear was used
by the pioneer orthodontists of the late 1800s
 By 1920 angle and his followers stopped using head
gear ( class II elastics)
 It was after world war II, Silas Kloehn’s impressive
results with head gear treatment of Class II
malocclusion

 In pre-adolescent child, extra oral appliances are
always applied to the first molar
 To be effective should be worn regularly for at
least 10-12 hrs per day
 Early evening to next morning
 Current recommended force 12 to 16 ounces or
350 to 450 gms per side

INDICATIONS
 Anteroposterior maxillary excess, or maxillary
protrusion.
 Normal mandibular skeletal and dental
morphology
 When there is continued active mandibular
growth, primarily disposing the mandible in a
forward, rather than downward direction.

Selection of head gear type
1. Head gear anchorage location
2. Head gear attachment to dentition
3. Bodily movement or tipping of teeth or
maxilla is desired

 The length and position of the outer head
gear bow and the form of anchorage
determine the vector of force and its
relation to the center of resistance of the
tooth

P. Parietal, O. Occipital, C. Cervical
Selection of head gear

Long face (skeletal open bite)
vertical maxillary excess
Two major diagnostic criteria
 Short mandibular ramus
 Rotation of the palatal plane (more posterior
growth) Most common
Restraining maxillary vertical development&
Encouraging antero -posterior mandibular growth

 Children with excessive face height generally
have normal upper face and elongation of max
and mand posteriors
 Unfortunately, vertical growth extends into the
adolescent and post adolescent years
Active retention

Hierarchy of effectiveness in long-
face class II treatment
HP Headgear to functional with
biteblocks
Bite blocks on functional
appliances
High-pull headgear to maxillary
splint
High-pull headgear to molars

Spontaneous correction of Class II
malocclusion
 Traditionally, clinicians viewed class II
malocclusion as primarily a saggital and vertical
problem
 Most Class II malocclusion in mixed dentition
patients are associated with max constriction.
(max width less than 31mm)

 Reichenbach and Taatz used the example
foot and shoe
Maxilla
Mandible

Are functional
appliances worth the
effort?

FLORIDA STUDY
 Children aged 9 years at the start of treatment
 Control, Bionator, Head gear with bite blocks
 The data revealed that both Bionator and
headgear treatment corrected cl II molar
relationship; reduced overjet and apical base
discrepancies.
 The skeletal changes that occurred were stable;
however the partime retention protocol used in
this study was not effective in preventing dental
relapse
Keeling, Wheeler et al. Anteroposterior skeletal and dental changes after early Class II treatment
with bionators and headgear. Am J Orthod Dentofacial Orthop 1998;113:40-50


A follow up study in 2003 of the same patients revealed that here was no significant differences in the final score when
patients who wore their headgear or bionator as a retention appliance between phase 1 and phase 2 treatment were
compared with patients who did not wear any appliance during this period

Most of the changes in PAR scores came from the finished results achieved regardless of the protocol or initial
severity of the malocclusion.

Patients who undergo 2 phase orthodontic treatment do not achieve better results than patients who undergo 1
FLORIDA STUDY

UNIVERSITY OF PENNSYLVANIA STUDY
 Efficacy of Headgear and Frankel app in the rx of Class II, div 1
 The common mode of action of these appliances is the possibility to
generate differential growth between the jaws
 The headgear, has a distal effect on the maxilla and first molars, but
not the maxillary incisors; the function regulator restrains the growth of
the maxilla and results in a retroclination of the maxillary incisors, a
more forward position of the mandible and a proclination of the
mandibular incisors.
 Increased maxillary intercanine distance and spacing among the
maxillary anterior teeth with headgear treatment. An increased
maxillary intermolar distance relates to different mechanisms with the
headgear (active force) than with the Fränkel FR (removal of cheek
pressure). The larger correction of the overjet with the Fränkel FR
occurred probably, and at least partially, because this appliance can
exert a distal force on the maxillary incisors.
J. Ghafari et al.Headgear versus function regulator in the early treatment of Class II, Division
1 malocclusion: A randomized clinical trial Am J Orthod Dentofacial Orthop 1998;113:51-61.

UNIVERSITY OF NORTH CAROLINA
STUDY
 Tulloch, Proffit, Philip et al initiated a randomized
controlled clinical trial in1997 in growing patients
with cl II malocclusion. Patients were randomly
assigned to one of the three groups.
 Group I received headgear treatment,
 Group 2 received functional appliance
 Group 3 received no treatment.

The significant findings of this study widely
publishing between 1997 and 2004 are as
follows
 There was no difference between the groups in the ANB
angle either at start or after phase 2 treatment.
 There was no differences in the quality of dental occlusion
between the children who had early treatment and those
who did not
 There was approximately the same distribution of successes
and failures with and without early treatment.

 Early treatment did not reduce the percentage of children
needing extraction of premolars or other teeth during phase 2
treatment.
 Early treatment did not influence the eventual need
for Orthognathic surgery.
There was very little differences in the time both groups
spent wearing fixed appliances.

The results of a RCT in 2003 involving 174 children divided into a
control group and a twin block group derived the following conclusions
•Appliances resulted in a reduction of overjet, correction of
molar relation and reduction in severity of malocclusion -
dentoalveolar change mostly and some favourable skeletal
change. The skeletal change was however not clinically
significant
•Early treatment resulted in an increase in self concept and a
reduction of negative social experiences.
•Subjects reported treatment benefits that could be related to
improve self esteem.
O’Brien, Right, Connoly, Harradiene et al. Effectiveness of early orthodontic treatment with the
Twin Block Appliance. AJO-DO 2003;124 (5) :488-94

 In conclusion there is very little evidence in
the literature to suggest the two phase
treatment can significantly modify growth or
eliminate the need for protracted phase two
treatment nor can it be justified to result is
fewer extractions or avoidance of orthognathic
surgery. Early phase one treatment is
beneficial in reducing the incidence of incisors
trauma and may have psychological benefits.

Class II Problems in
Adolescents
(12-15yrs)

FOUR MAJOR APPROACHES
1. Growth modification with head gear or
functional appliances
2. Distal movement of maxillary molars, and
eventually entire upper dental arch
3. Retraction of maxillary incisors into a
premolar extraction space, and
4. A combination of retraction of the upper teeth
and forward movement of the lower teeth

Growth modification in adolescents
 Growth modification would be more successful
when more growth remains
 As a general guideline, even in the most favorable
circumstances it is unlikely that half of the changes
needed to correct Class II malocclusion in an
adolescent would be gained by differential growth (
3-4mm from differential mandibular growth )

 Head gear is compatible with fixed appliances
but most functional appliances are not.
 If a functional appliances is desirable for
adolescent treatment, often a fixed functional
that allows brackets on the incisor teeth is the
best choice.

FLEXIBLE
JASPER JUMPER
AMORIC TORSION COILS
ADJUSTABLE BITE CORRECTOR
SCANDEE TUBULAR JUMPER
KLAPPER SUPER SPRING
THE BITE FIXER
CHURRO JUMPER
RIGID
HERBST APPLIANCE
CANTILEVERED BITE JUMPER
MALU HERBST APPLIANCE
VENTRAL TELESCOPE
MANDIBULAR PROTRACTION APPLIANCE
MAGNETIC TELESCOPIC DEVICE
BIOPEDIC APPLIANCE
MARA
HYBRID
CALIBRATED FORCE MODULE
EUREKA SPRING
TWIN FORCE BITE CORRECTOR
FORSUS
ALPERN CLASS II CLOSERS
SABBAGH UNIVERSAL SPRING

Fixed functional appliance is a powerful tool for non-
surgical, non-extraction, adult Cl-II Div 1 malocclusion
Indications-
Mild Skeletal Cl-II or Skeletal Cl-I
Dental Cl-II Div 1 with overjet up to 11mm
Normal or horizontal grower
Little or no crowding
Cooperative attitude
Ruf & Pancherz AJODO 126:140-152, 2004

EFFECTS OF HERBST APPLIANCE :
 Normalization of occlusion is generally accomplished with 6 to 8
months of treatment. Over corrected sagittal dental arch relationship
and incomplete cuspal interdigitation at the end of treatment are to
be expected before settling occurs.
 Improvement in sagittal and vertical occlusion relationships during
treatment is a result of both skeletal an dental changes (Pancherz,
1982).
Sagittal Changes
Skeletal
 Restrains maxillary growth and decrease of SNA angle.
 Increases mandibular length (Pancherz 1979, 1981, 1982) which
can be attributed to condylar growth stimulation as an adaptive
reaction to the forward positioning of mandible.

DENTAL
 The telescope mechanism produces a posterior directed force on the upper
teeth and an anterior directed force on the lower teeth, resulting in distal
tooth movements in the maxillary buccal segements and mesial tooth
movements in the mandible.
1. Arch Perimeter :
 The distalizing forces of the telescope mechanism of the Herbst appliance
on the upper 1st molars and anteriorly directed forces on the lower front
teeth, tend to increase arch perimeters in the maxillary and mandibular arch
during treatment (Hansen et al. 1995).
2. Arch Width :
 Hansen et al (1995) : During treatment the maxillary and mandibular dental
arches expand laterally in both canine and molar areas.

VERTICAL CHANGES :
a) Skeletal :
 Increase in lower anterior facial height (LAFH) due to eruption of
lower posterior teeth.
 Increase in gonial angle.
b) Dental
 Overbite reduction is primarily accomplished by intrusion of lower
incisors and enhanced eruption of lower molars.
 Part of the registered changes in the vertical position of the
mandibular incisors results from proclination of these teeth.
 Because of vertical dental changes, maxillary and mandibular
occlusal planes tip down.

•During treatment with the Forsus™ spring the maxilla undergoes a
minimal increase in length anteriorly
•A retrusion of the upper incisors with labial tipping of the roots can
shift the A point so far forward as to mask the real effect of the backward
displacement of the maxilla.
•Consolidation of all teeth in the maxillary arch by means of a
multibracket appliance into one unit shifts the point of force application
downwards and backwards with respect to the unit’s center of resistance.
That is why both the incisors and the molars tip distally during treatment
with these Class II appliance systems
•The headgear effect of these types of Class II devices is thus also
confirmed for the Forsus™ spring.
Nina Heinig, Gernot Göz.Clinical Application and Effects of the ForsusTM Spring.A Study of a
New Herbst Hybrid. J Orofac Orthop 2001;62:436–50
TREATMENT EFFECTS WITH THE FORSUS APPLIANCE

•During treatment with the Forsus™ spring the mandible shifts to
anterior (SNB). Since the mandible grows more in forward direction than
the maxilla, the jaw relationship is improved.
•The effective increase in mandibular length (pg) was 1.2 mm.
•marked protrusion of the lower incisors (L1-MeGo, ii), since the force
vector of a spring on a continuous mandibular arch is slightly above the
center of resistance at the level of the clinical crown, resulting in
increased protrusion of the incisor
•The lower molars drifted to mesial

•There was noticeable tipping of the occlusal plane which, measured at
the anterior cranial base, underwent a rotation in terms of a bite opening.
• This opening movement is dentally induced. The pushing effect of the
spring on the upper molars and on the lower incisors intrudes these teeth
with consequent tipping of the occlusal plane.
•The overbite was decreased by 1.2 mm, which can be ascribed to the
intrusion and protrusion of the lower incisors

•In the present study 33% of the reduction in overjet was skeletally (ss
plus pg) and 66% dentally induced (is-ss plus iipg).
•The improvement in molar relationship was 39% due to skeletal
changes (ss plus pg) and 61% due to dental movements (ms-ss plus mi-
pg).
•The correction of the malocclusion was thus due mainly to
dentoalveolar effects in the upper and lower jaws and, to a lesser extent,
to the altered position of the mandible.

•During treatment with the Forsus™ spring the upper dental arch is
expanded. The lower arch is also expanded as a result of interdigitation
with the upper jaw
•If no broadening of the dental arch is desired, then a transpalatal arch
must be inserted

Paola Cozza, Tiziano Baccetti, Lorenzo Franchi, Laura De Toffol, and James A. McNamara.
Mandibular changes produced by functional appliances in Class II malocclusion:A systematic
review. Am J Orthod Dentofacial Orthop 2006;129:599.e1-599.e12)
On the basis of the analysis of 22 retrieved articles,
it can be concluded that:
1. Two-thirds of the samples in the 22 studies reported clinically significant
supplementary elongation in total mandibular length as a result of overall
active treatment with functional appliances.
2. The short-term amount of supplementary mandibular growth appears to be
significantly larger when the functional treatment is performed at the
adolescent growth spurt.
3. None of the 4 RCTs reported clinically significant supplementary growth of the
mandible induced by functional appliances.
4. The Herbst appliance showed the highest coefficient of efficiency (0.28 mm per
month) followed by the Twin-block (0.23 mm per month)

 The appliances used for molar distalization can
be divided into
 Removable appliances and
 Fixed appliances.
Removable appliances are:
 Extra oral traction
 Removable appliances with finger springs
 Sliding jigs with intermaxillary elastics.

The fixed appliances are
A. Intramaxillary appliance
1. Wislons 3D appliance
2. Repelling Magnets
3.The pendulum appliance
4. Niti based appliances : archwires – single loop,
double loop; Compressed coil springs
5. Jones jig
6. Distal Jet
7. Fixed piston appliances
8. IBMD 9. K-loop 10. Distalix
11.Franzulum appliance 12. Lokar appliance
13. First class appliance 14. Carriere’s Distalizer

B. Intermaxillary appliance:
1. Herbst appliance
2. Jasper Jumper
3. Eureka Spring
4. Klapper superspring
C. SAS supported distalization:

DISTALIZATION DIAGNOSIS
 The first step is to confirm the diagnosis of a
forward maxillary molar position.
 1. Check the centric relation position (and
vertical status). Before considering the molar
relationship in terms of dental or skeletal
malocclusion, it is desirable to check the TMJ
status. All records must be correlated, ie,
cephalo-metrics, functional axiographics, and
radiologic exams (MRI, CT scan).

 Korn has cautioned against using
extraoral force in patients with
undiagnosed meniscus disorders who
are borderline clickers with an "end-on
click.
 a. Korn has shown that the distalization
may push back the maxillary molar ----
 b. causing more posterior tooth
contacts and then moving the condyle
backward into a more posterior
position, now with a "true click”.
 c. The mandible then assumes its
normal position, but the meniscus is
now too far forward.

 2. Check the sagittal relationship.
(1) The pterygoid vertical plane (PTV)/maxillary molar
relationship and
(2) the convexity prognosis.
 According to Ricketts, the normal maxillary molar (M1)
position is given by the distal face of the molar to the
PTV. The clinical norm is age + 3 mm, and clinical
deviation is 3 mm.
 In good skeletal and dental Class I relationships, the
facial axis normally crosses the mesial cusp of M1.
 However, the maxillary molar analysis must not be
static only, but also dynamic. If the distance M1/PTV is
shorter than the normal measurement, the possibility
for distalization is low and possible extractions will
depend on growth potential and the presence of 3rd
molar.
 Therefore, posterior dental arch analysis must include
mesiodistal measurement of all molars to determine the
posterior space available at maturity

INDICATIONS & CONTRAINDICATIONS
THE INDICATIONS FOR MOLAR
DISTALIZATION
 1. In non-extraction treatment of Class II malocclusion
cases.
 2. In low & average mandibular plane angle cases.
 3. In class I skeletal pattern cases.
 4. In patients with mild arch length discrepancy.
 5. In cases where the upper permanent molars have
moved mesially due to early loss of deciduous molars.
 6. In patients where the second molars extractions are
planned or where it has not yet erupted.
 7. In second molar extraction cases where the third
molars are well formed and erupting properly.

CONTRAINDICATIONS FOR MOLAR
DISTALIZATION
 In high mandibular plane angle cases.
 Skeletal and Dental open bite
 Severe Class II & III skeletal pattern
 Severe arch length discrepancy patients.

INFLUENCE OF 2ND
MOLAR ON
DISTALIZATION OF 1ST
MOLAR
 A controversy exists concerning the influence of second molars on
the distal movement of the first molars.
 Graber noted that extraoral traction on the first molars, when the
second molars have not totally erupted, led to distal tipping only and
not to bodily distal movement. Bondemark et al (AO 94 Magnets vs
NiTi coils) stated that the presence of second molars did influence
tipping and distal movement of the first molars.
 Gianelly (AJO 91 NiTi coils) also found that treatment time was
increased with the presence of second molars.
 Muse et al (AJO 93 Wilsons BDA) found that the presence of
maxillary second molars did not correlate with the rate of maxillary
first molar movement or with the amount of tipping that occurred.

CAMOUFLAGE DENTAL TREATMENT OF
CLASS II MALOCCLUSION
The goal of dental camouflage is to disguise the unacceptable
skeletal relationship by orthodontically repositioning the teeth in
the jaws so there is an acceptable dental occlusion an aesthetic
facial appearance.
Camouflage treatment may involve
•Class II elastic traction
•Non extraction Line of treatment
•Extraction Line of treatment

PATIENT SELECTION FOR CAMOUFLAGE
TREATMENT
•Older adolescents or adults who no longer have adequate facial growth
potential.
•Skeletal Class II is mild to moderate in severity
•Minimal dental crowding so that all space available is used for
anteroposterior correction
•Individuals with normal vertical proportions.

INTERARCH TRACTION
•Extends from the anterior part of the maxillary arch to the posterior part
of the mandibular arch, commonly referred to as Class II elastics.
•Ant force to the mandible and posterior force to the maxilla

EFFECTS OF CLASS II ELASTICS
Initially it was thought to have a stimulating effect on the mandibular
condylar cartilage bringing about clinically relevant mandibular
lengthening (Pancherz et al)
However Hanes showed that the change was purely dentoalveolar.
The dental changes include
•Lower molar extrusion alongwith buccal tipping
•Clockwise rotation of the occlusal plane
•Increase in MP angle and LAFH
•Extrusion of upper incisors
•Protrusion of lower incisors

The dental changes improve occlusal relationship by
•Correcting molar relationship
•Reducing Overjet
•Mild retraction of the upper anterior segment
The magnitude of force required depends on the clinical situation
Single tooth movement – 3-4oz per side
If groups of teeth are to be moved up to 250 gms of force may be used

Birgitta Nelson, Ken Hansen and Urban Hägg. Class II correction in patients treated with Class II
elastics and with fixed functional appliances: A comparative study. Am J Orthod Dentofacial
Orthop 2000;118:142-9
Class II elastics

DENTAL CAMOUFLAGE WITHOUT
EXTRACTIONS
•Mild Skeletal Class II
•Class II div 2 malocclusion with excessive overbite
•Mild overjet of 6-8 mm
•Upright lower incisors
•Presence of interdental spacing
Appliance design involves maximum maxillary posterior anchorage with
maximum mandibular anterior anchorage
This is to minimize mesial movement of the max molars while the
premolars canines and incisors are retracted.

REINFORCING MAXILLARY POSTERIOR
ANCHORAAGE
•Face bow or J hook headgear
•TPA or nance palatal arch
•Uniting posterior teeth to form a unit
•Segmented mechanics for reduced friction
•Distal crown tipping of the max anteriors followed by their
uprighting to minimize strain on anchorage
•Class II elastics for inter arch anchorage
•Implant anchorage

NON EXTRACTION TREATMENT OF CLASS II,
DIVISION 2 MALOCCLUSION
The aims of treatment in Class II div 2 malocclusion involve
1. Relief of crowding
2. Reduction of overbite
3. Reduction of interincisal angle to 125-130
4. Bring the centroid of the upper incisor lingual to the lower incisor tip
5. Correct buccal segment relationship to Class I
6. Correct any scissor bites
7. Support the facial profile
S Barnett. Rationale of treatment for Class II Division 2 malocclusion. BJO, 1991; 18:173-81

Space requirements are
satisfied by
•Arch expansion
•Anteroposterior arch
lengthening by
advancement of lower
incisors

DENTAL CAMOUFLAGE WITH EXTRACTIONS
The decision to extract is based on
•Reduction of upper lip procumbency
•Relief of crowding
•Reduction in overjet
•Establishing molar relation
•Ideal interincisal angulation

UNIARCH EXTRACTIONS involving the extraction of the upper first
premolars are preferred if
•Overjet of 8- 10 mm
•Minimal lower anterior crowding
•Protrusion of the upper anteriors
•Upright lower incisors
•Absence of spacing in the upper arch
The treatment goal is to maintain the molars in a Class II molar
relationship but to achieve complete reduction of overjet
Upper second molars can also be extracted followed by retraction of all
the upper teeth into the extraction space assisted by implant anchorage if
the third molars are well developed and in proper alignment

Extraction in both arches involving all first bicuspids or upper first
PM and lower 2nd
PM is also an option.
Molar correction to Class I can be achieved
Extraction in the lower arch is needed if crowding or lower incisor
protrusion is present
Lower 1st
PM – Crowding /Lower incisor protrusion
Lower 2nd
PM- Mild lower incisor protrusion/Mainly molar correction

SURGICAL CORRECTION
OF CLASS II SKELETAL
PROBLEMS

Clinical Management Of Some
Commonly Encountered Class II
Surgical Problems
1. Mand. Deficiency with normal or reduced
facial height
2. Excessive face height (long face)

Mand Deficiency with normal or
reduced facial height
 Horizontal growth pattern
 Class II molar and Canine relationship –
often with a div. 2 pattern.
 Excessive curve of spee in the lower arch.
 Incisor crowding
 Deep bite – usually causing some gingival
irritation

 Chin button well developed
 Deficiency near the lower lip region
– seen as a deep mentolabial
sulcus, a curl of the lower lip and
an aged appearance.
 TMJ disorders – (disputed)

Surgical plan
 In most of these patients, -
Mandibular deficiency needs to be corrected
Height of the face must be increased.

Mandibular subapical procedure vs. BSSO
Subapical procedure
When face ht. is not to be increased
BSSO
To increase face height

 Rotation of mandible chin moved back and
incisors forward
 Genioplasty if needed
• Reduce chin prominence
• Further increase face height
 No maxillary surgery to increase face height

Long Face Problems
 Vertical excess of post
maxilla
 ↑mand plane angle
 Incisor exposure
 Incompetent lips
 Gummy smile
 Narrow maxilla
 Cross-bite

Long Face Problems
Surgical considerations
 impacting to maxilla – mandibular
autorotation
 Rotating the mandible upwards and
forwards after a BSSO
 Chin procedures

Pre surgical Orthodontics
 Orthodontist must know 2 things –
Maxilla in 1 piece or segmented? – how many
pieces, and where
Chin position? - or is proper lip – chin balance
going to be achieved by orthodontic
treatment
Long Face Problems

 Maxillary impaction
↑ wrinkles on the cheek
Drastic reduction in incisor exposure
Widening of alar bases – Compensated by an
alar cinch procedure
Aged appearance
More tolerated in young adults
Long Face Problems

 If maxilla is moved back - ↓lip support
 Maxillary teeth may have to be positioned
so as to get good lip support
 Genioplasty – avoid major jaw surgery
Long Face Problems

EXTRA ORAL PHOTOGRAPHS
PRE TREATMENT
PRESENT STAGE

PRE TREATMENT PRESENT STAGE
LATERAL CEPHALOGRAM

PRE AND POST TREATMENT COMPARISON

 61 patients
 BSSO only, no additional procedure performed, and
Rigid internal fixation (RIF) followed for 3 years after
surgery
 20 patients (20.8 + 4.8) - Low angle group
 20 patients (43 + 4) - High angle group
 Remaining 21 patients in the normal group
 Stability of increasing MPA
Mobarak, Espeland, Krogstad and Lyberg. Mandibular advancement surgery in
high angle and low angle Class II patients: Different long term skeletal
responses. AJO 2001

 Dental changes
retroclination of the lower incisors, while the upper
incisors remained more or less upright.
responses. AJO 2001
Timing of relapse –
 Low angle group about 98% of the relapse
occurred within the first 2 months
 High angle group, the relapse was more
gradual –
 30 % in the first 2 months
 25 % between 2 months to 1 year
 38% in the between 1 year to 3 years

 Relapse due to –
Intersegment mobility
Distraction of condyle
 Most of the relapse due to repositioning of condyle in
fossa
 Other possible causes for late changes
late mandibular growth in the original direction
residual effects of incompletely adapted suprahyoid
musculature
Condylar resorption
responses. AJO 2001

Hans Pancherz, Sabine Ruf, Christina Erbe, Ken Hansen.The Mechanism of Class II
Correction in Surgical Orthodontic Treatment of Adult Class II, Division 1 Malocclusions.
Angle Orthod 2004;74:800–809.)
The purpose of this investigation was to assess the dentoskeletal effects and facial
profile changes as well as the mechanism of Class II correction in adult Class II
subjects treated by surgical mandibular advancement in combination with orthodontics.
(1)The mandibular prognathism enhanced;
(2)The sagittal interjaw base relationship improved;
(3) The mandibular plane angle increased;
(4) The lower anterior facial height increased;
(5) The lower posterior facial height decreased;
(6) The facial profile straightened;
(7) The overjet and Class II molar relationship were corrected.
Overjet reduction was accomplished by 63% skeletal and 37% dental changes.
The Class II molar correction was accomplished by 81% skeletal 19% dental changes.

•The percentages of patients with a long-term increase in overbite
were almost identical in the orthodontic and surgery groups, but the
surgery patients were nearly twice as likely to have a long-term
increase in overjet.
•The patients’ perceptions of outcomes were highly positive in both
the orthodontic and the surgical groups.
•The orthodontics-only (camouflage) patients reported fewer
functional or temporomandibular joint problems than did the surgery
patients and had similar reports of overall satisfaction with treatment,
but patients whohad their mandibles advanced were significantly
more positive about their dentofacial images.
Colin A. Mihalik, William R. Proffit, and Ceib Phillips.Long-term follow-up
of Class II adults treated with orthodontic Camouflage: A comparison with orthognathic
surgery outcomes. Am J Orthod Dentofacial Orthop 2003;123:266-78

•All surgery and Herbst subjects were treated successfully to Class I occlusal
relationships with normal overjet and overbite.
•In the surgery group, the improvement in sagittal occlusion was achieved by
skeletal more than dental changes; in the Herbst group, the opposite was the case.
•Skeletal and soft tissue facial profile convexity was reduced significantly in both
groups, but the amount of profile convexity reduction was larger in the surgery
group.
•The success and predictability of Herbst treatment for occlusal correction was as
high as for surgery. Thus, Herbst treatment can be considered an alternative to
orthognathic surgery in borderline adult skeletal Class II malocclusions,
especially when a great facial improvement is not the main treatment goal.
Sabine Ruf and Hans Pancherz.Orthognathic surgery and dentofacial
orthopedics in adult Class II Division 1 treatment: Mandibular sagittal split
osteotomy versus Herbst appliance. Am J Orthod Dentofacial Orthop

MANDIBULAR DISTRACTION
 Mandibular distraction is a safe and effective surgical
technique. For patients with Treacher Collins, Pierre
Robin, Nager and Craniofacial microsomia syndromes
undergoing surgical reconstruction of the hypoplastic
mandible by distraction, the length of hospitalization and
operating time has been drastically reduced.

 From the age of 2 to 6 years,mandibular distraction
osteogenesis can be considered in severe conditions with
associated sleep apnea or tracheostomy.
 However if distraction occurs at this age interval,it is likely
that a secondary distraction will be required after post
pubertal facial growth, because it is unlikely that the
mandibular development will keep up with the growth of the
remainder of the facial skeleton.
 Mandibular distraction during the teenaged years should
be post poned until the patient has reached skeletal
maturity.
 In girls, this typically occurs around 15 years of age and in
boys around the age of 17 years.

Indications for surgery in the teen years include
Residual postsurgical relapse or abnormal growth
unsatisfactory bone contour
Malocclusion
 In patients with minimal mandibular deformities,
classic orthognathic procedures are indicated.
 Mandibular distraction should be considered in
patients with moderate to severe skeletal
deficiency or bilateral disease in whom pressure
from the soft tissues would significantly increase
the risk for post operative graft resorption or
relapse of bony fixation.

MANDIBULAR DISTRACTION-DEVICES

 4) Tooth-Borne appliances:
- Razdolsky-1997- Introduced a completely tooth borne IO distractor
capable of linear changes(ROD device)
- Current technique starts by fitting preformed SS crowns to one tooth on
either side of the anticipated osteotomy site
- A rubber base impression is then taken & a IO distractor is fabricated in
the laboratory

W. H. Schreuder, J. Jansma, M. W. J. Bierman, A. Vissink: Distraction
osteogenesis versus bilateral sagittal split osteotomy for advancement of the
retrognathic mandible: a review of the literature. Int. J. Oral Maxillofac. Surg.
•Patient comfort
•Time
•Surgeon comfort
•Relapse
•Duration of Treatment

There is no one ideal method for treating ClassII
malocclusion.
Following clinical examination ,a precise analysis of
cephalometric radiographs and dental casts should be
undertaken to identify the components of the malocclusion
that deviate from “normal”
Then clinician can select the appropriate treatment
regimen from among a no. of options.

Class 2 malocclusion

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