This document provides an overview of class III malocclusions, including definition, etiology, classification, clinical examination, and treatment approaches. It discusses pseudo and skeletal class III malocclusions. Treatment options covered include functional appliances like Frankel III regulator, chin cup, and face mask therapy. It also discusses camouflage treatment approaches like non-extraction and extraction methods. The goal of early interceptive treatment is preventing worsening and providing favorable growth. Functional appliances aim to redirect mandibular growth. Camouflage treatments disguise the underlying skeletal deformity through dental movements.

2. CONTENTS
 INTRODUCTION
 DEFINITION
 ETIOLOGY
 FREQUENCY
 CLASSIFICATION
 CLINICAL EXAMINATION
 GROWTH COSIDERATION
 GOALS OF EARLY INTERCEPTIVE TREATMENT
 TREATMENT OF PSEUDO CLASS III MALOCCLUSION
 TREATMENT OF SKELETAL CLASS III MALOCCLUSION
 CONCLUSION
 REFERENCE

3. INTRODUCTION
 Orthodontic treatment not only involves
establishment of physiologically and
anatomically functional occlusion but also
includes correction of the relationship of the
maxilla and mandible to each other and to the
rest of the craniofacial complex.

4. DEFINITION
 According to Angle (1899): Class III
malocclusion occurred when the lower
teeth occluded mesial to their normal
relationship by the width of one premolar
or even more in extreme cases. (mesio-
occlusion)

5. ETIOLOGY
 GENITIC
 McGuigan (1966) – Inheritance of class III
malocclusion in Hapsburg Family, having
the distinct characteristics of prognathic
lower jaw.
 Litton et al (1970) – Dental characteristics
of class III are related to genetic
inheritance.

6.  Rakosi & Schilli (1981) environmental
factors: Habits and mouth Breathing
 Enlarged tonsils and naso-respiratory
diseases.
 Premature loss of deciduous molars:
Results in anterior mandibular
displacement.

7.  TERATOGENS:
 Cleft lip and palate result in maxillary deficiency in most occasions a
class III malocclusion is established. Teratogens causing cleft lip and
palate are aspirin, cigarette smoke (hypoxia), Dilantin, 6-
Mercaptopurine, valium etc
 Vitamin D excess causes premature closure of sutures and
might lead to class III malocclusion

8.  ACROMEGALY AND HEMI MANDIBULAR
HYPERTROPHY:

9. FREQUENCY
 Caucasians - 1 to 4 %
 African – Americans - 5 to 8%
 Asians:
 Japanese: 4 % younger / 14 % older
 Chinese: 3 % younger / 13 % older
 Indians: 1.3% (J Ind. Ped & Prev Dent: 1998 – Uteraja et
al)
 Iranian: 2.1% (East Mediters Health J: 2006: Danaie et al)

10. CLASSIFICATION
Generally of 2 types:
 Dentoalveolar
 Skeletal
 Mandibular protrusion
 Maxillary retrusion
 Combination

12.  PSEDUO CLASS III
Malocclusion is produced by a forward movement of
mandible during jaw closure.
Also known as habitual or postural class III malocclusion.

13.  Angles classification
 The mesio – buccal cusp of the maxillary first
permanent molar occluding in the inter dental space
between the mandibular first and second molars.

14.  Class III Modification of Dewey

15. MOYERS CLASSIFICATION
ACCORDING TO THE CAUSE
OSSEOUS
MASCULAR
DENTAL

16. CLINICAL EXAMINATION
 EXRAORAL FEATURES:
 A CONCAVE FACE,DEFICIENT MAXILLA OR PROMINENT CHIN.
 MALAR DEFICIENCY RESULTING INTO FLAT FACE
 INCREASED LOWER ANTERIOR FACIAL HEIGHT
 ANATOMICALLY LARGE LOWER LIP LENGTH

17.  INTRAORAL FEATURES
 ZERO OR –VE OVERJET
 NARROW MAXILLARYARCH WITH CROWDING
 UNILATERAL OR BILATERAL POSTERIOR CROSSBITE
 PROCLINED MAXILLARY INCISORS
 RETROCLINED MANDIBULAR INCISORS
 LOW TONGE POSTURE

 FLAT CURVE OF SPEE.

18. GROWTH COSIDERATIONS
 Sugawara and Mitani :Reported similar increments
between patients with Class III and Class I malocclusions
during the prepubertal pubertal and postpubertal growth
periods.
 Battagel :found that the largest increment of facial
growth for males occurred between the ages of 14 and 16
years.
 whereas in female patients the maximum increment of
facial growth occurred between the ages of 9.5 to12 years,
although active growth continued in the nasal area and
both jaws after the age of 15 years.

19. Goals of early interceptive treatment
 (1) preventing progressive, irreversible soft tissue, or
bony changes.
 (2) improving skeletal discrepancies and providing a more
favourable environment for future growth.
 (3) improving occlusal function;
 (4) simplifying phase II comprehensive treatment
 and minimizing the need for orthognathic surgery
 (5) providing more pleasing facial esthetics

20. DIAGNOSTIC CRITERIAFOR PSEUDO CLASS III

21. TREATMENT OF PSEUDO CLASS III
MALOCCLUSION
 Elimination of the CO-CR discrepancy.
 REVERSE STAINLESS STEEL CROWNS.
 TONGUE BLADE

22.  INCLINED PLANES.
 AUXILLARY SPRINGS

23. TREATMENTOF SKELETALCLASS III MALOCCLUSION.
FUNCTIONAL APPLIANCE THERAPY

24. FRANKELIII REGULATOR
 The purpose of lip pad are threefold.
 TO ELIMINATE RESTRICTIVE PRESSURE OF UPPER LIP ON
THE MAXILLA.
 TO EXCERT PRESSURE ON THE TISSUE AND PERIOSTEAL
ATTACHMENTS FOR STIMULATING BONE GROWTH.
 TO TRANSMIT UPPER LIP FORCE TO THE MAXILLA VIA THE
LOWER LABIAL ARCH FOR A RETRUSIVE STIMULAS.

25.  The FRIII appliance can also be used as a retentive device
following maxillary protraction treatment.
 FRIII appliance was constructed to maintain the antero-
posterior and transverse corrections until the maxillary
incisors were fully erupted with sufficient overbite to
maintain the Class III correction.

26. CLASS III OR REVERSED BIONATOR.
 Encourage development of maxilla Bite opened
2mm for this purpose
 Acrylic portion Extends incisally from canine to
canine behind the upper incisors
 Acrylic is trimmed away by 1mm behind the
lower incisors to prevent the tipping

27.  Palatal bar
Runs forward with loop extending as far as
dec 1st m or premolar
Function – tongue to contact anterior portion
of palate , encouraging forward growth of this
area.

28.  Labial bow
 In front of lower incisors
 Wire slightly touches the labial surface lightly / it is at a
paper thickness away

29.  Construction bite
 Construction bite- taken in more retruded position so as to
allow labial movement of maxillary incisors &also to
exert restrictive force on lower arch.

30. CHIN CUP
 Skeletal Class III malocclusion with a relatively normal
maxilla and a moderately protrusive mandible can be
treated with the use of a chin cup.
 The objective of early treatment with the use of a chin cup
is to provide growth inhibition or redirection and
posterior positioning of the mandible.

31. Effects on Mandibular Growth
 Redirection of mandibular growth vertically.
 Backward repositioning (rotation) of the
mandible.
 Remodelling of the mandible with closure of the
gonial angle

32.  EFFECT ON MAXILLA
 Uner,Yuksel,and Ucuncu (Eur J Orthod 17:135-141, 1995)
 Showed that early correction of an anterior crossbite with
a chin cup appliance prevents retardation of antero-
posterior maxillary growth.
 Sugawara et a1 (Am JOrthod Dentofacial Orthop 98:127-133, 1990.)
 Compared the growth changes of patients after chin cup
treatment with control subjects and reported that, at age
17, the midface is more deficient in patients of the control
groups than in those of the treatment groups.

33.  Force Magnitude.
 CHIN CUP 2 TYPES
 OCCIPITAL PULL CHIN CUP.
 VERTICAL PULL CHIN CUP.
 300-500g PER SIDE
 14hr/day

34. PROTRACTION FACE MASK THERAPY
 Extraoral appliance that utilizes rests on the
chin and forehead(and occasionally the cheek
bones) as anchorage for elastic traction, with
the purpose of orthopaedically protracting the
maxilla.
 Glossary of Orthodontic Terms

35.  The use of a protraction face mask was first
described more than 100yrs ago in 1875 by
Johnson et al.
 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.

36.  Although the facial mask was developed over 100
years ago, this approach was used infrequently
until reintroduced by Delaire in early 1970’s
 Petit 1983: modified the basic concept of Delaire
by increasing the amount of force generated by
the appliance and decreasing the total treatment
time

37.  1987 McNamara: introduced the use of a
bonded expansion appliance with acrylic
occlusal coverage for maxillary protraction.

38. ANATOMICAL CONSIDERATIONS
 Circum-maxillary Sutures
A. Frontomaxillary
B. Nasomaxillary
C. Zygomaticomaxillary
D. Zygomaticotemporal
E. Pterygopalatine
F. Intermaxillary
G. Ethmomaxillary
H. Lacrimomaxillary

39. Melsen 1975 AJO
Proffit 5th Edition

40. BIOMECHANICALCONSIDERATION
 The orthodontist must first decide, whether to protract with a
clockwise moment on the maxilla, a counter clockwise
moment, or no moment
.
 If the patient has normal overbite and normal vertical
proportions, protraction without any moment is indicated.
 If the patient has an anterior open bite in addition to the
maxillary deficiency, a clockwise moment should be used.
 If the patient has a deep bite, a counter clockwise moment
should be chosen.
Staggers JCO 1992

41. FACE MASK COMPONENTS
Forehead Piece
Main Frame
Protraction Bar
Chin Cup

42.  Centre of Resistance of Maxilla
 The center of resistance of the maxilla was found to be located at the
distal contacts of the maxillary first molars one half the distance from
the functional occlusal plane to the inferior border of the orbit.

43.  Magnitude of Force
 The sutural anatomy and age of the patient play a major role in
determining the amount of force needed to bring the maxilla forward
with the protraction forces.
 Preadolescent patient (5-8yr) – 200-250gm
 Early adolescent patient (8-11yr) – 300-350gm
 Late adolesent patient (12yr and above) – 450-600gm
Bishara

44.  Duration of Force
 Most of the studies done recommend a minimum of
10-12 hours/day preadolescents
12-16 hours/day adolescents
McNamara Brudon

45.  Treatment Timing
 Takada et al EJO 1993 : Reported that face mask treatment is most
effective in prepubertal patients (mean age, 7.8 years) and pubertal
patients (mean age, 10.3 years) and becomes less effective after late
puberty.
 Baccetti 1998: Showed that treatment of class III malocclusion with
bonded maxillary expander and face mask in the early mixed dentition
results in a more favourable craniofacial changes than treatment in
late mixed dentition

46.  Turley 1998 AJODO: Cephalometric effects of face
mask/expansion therapy in Class III children: a
comparison of three age groups (4-7 years, 7-10 years, 10-
14 years)Most effective in younger age groups but
significant change in older groups too.
 Franchi AJODO2004: it was shown that significant
maxillary advancement could be achieved orthopedically
only by treating Class III patients during the deciduous or
early mixed dentition phases.

47. DESIGNS
Delaire mask was popularized to protract
the maxilla in 1978
In this appliance design,
Extraoral anchorage regions were the chin
and forehead.

48. The intraoral part of the appliance was
constructed with 1 mm stainless steel
arches (buccal and lingual) soldered to
the upper molar bands, which were
cemented to the anchor teeth (1st
permanent or 2nd deciduous molars).
McNamara Brudon

49. The protraction elastics were attached
between theanterior hooks (facing the
distal side of the lateral incisors) soldered
on the intraoral arch, with the hooks on the
Pre labial arch of the mask placed at the
level of the labial commissural line.
To avoid an opening of the bite, the force,
which delivers about 400 g of force on
each side was directed downward about
20° to25° to the occlusal plane.
Delaire 1971

50.  Petit Face Mask 1983
The Petit facial mask was originally
constructed on a patient-by-patient
basis, using .25" round lengths of
stainless steel, to which pads for the
forehead and chin were attached

51. video

52. CLASS III CAMOUFLAGE TREATMENT
 Treatment approach were the underlying skeletal
deformity is left untreated but teeth are moved to such
positions to create an acceptable occlusion with out
violating the norms of aesthetics and stability is
categorised as camouflage treatment.

53. Treatment approaches
2 Approaches.
NON EXTRACTION
EXTRACTION

54.  NON EXTRACTION APPROACH
1.THE MEAW TECHNIQUE
 INTRODUCED BY KIM IN 1987
 IT S AN IDEAL EDGEWISE ARCH WIRE WITH ADDITION OF
BOOT LOOPS.
 THE VERTICAL LOOPS COMPONENT SERVES AS A
BREAKBETWEEN THE TEETH,GIVES FLEXIBILITY TO THE
ARCH WIRE,AND ALLOW HORIZONTAL CONTROL OF THE
TOOTH POSITION
 IT WAS ORIGINALLY PRESCRIBED FOR BRACKETS WITH
0.18 INCH SLOTS AND 0.16 X 0.022 INCH ARCH WIRE
ALLOWING MORE FLEXIBILITY FOR INTRUSIVE FORCE.

55.  USE OF DISTALIZATION OF LOWER ARCH USING
ANCHORAGE DERIVED FROM MINI IMPLANT
 THE TADS HAVE PROVED USEFUL IN PROVIDING ANCHORAGE
REQUIRED TO DISTALIZE THE WHOLE MANDIBULAR ARCH
INCLUDING SECOND MOLAR.
 THE PRESENCE OF THIRD MOLARWILL HAVE TO BE EVALUATED
AND IF NEEDED BE,IT MAY REQUIRE SURGICAL CORRECTION.

56.  EXTRACTION APPROACH.
 DEPENDING ON THE REQUIREMENT OF THE CASE
EXTRACTION CHOICES COULD BE.
MANDIBULAR INCISOR
UPPER SECOND AND LOWER FIRST BICUSPIDS
LOWER FIRST BICUSPIDS
MANDIBULAR SECOND MOLARS

57. MANDIBULAR INCISOR EXRACTION
 SITUATIONS WHERE CROWDING IS NOT LARGE OR
SITUATIONS OF BOLTONS DICCREPANCY.
 UPPER/LOWER MIDLINE MISMATCH
 LONGTERM RIGID LINGUAL RETAINER AS MANDIBULAR
ARCH WITH THREE INCISORS HAS A TENDENCY FOR
LINGUAL COLLAPSE.

58.  UPPER SECOND AND LOWER FIRST BICUSPIDS.
 TO RESOLVE LARGE MANDIBULAR CROWDING,AND
INDUSE SIGNIFICANT TIPPING OF MANDIBULAR ARCH.
 MAXILLARY ARCH WHICH HAS LESSER CROWDING,
CONSIDERD FOR SECOND PRE MOLAR EXTRACTION.

59.  LOWER FIRST BICUSPIDS
 WHEN UPPERARCH ISWELL ALIGNED OR CAN BEWELL
ALIGNEDWITH DENTAL EXPANSIONOFTHE ARHES.
 LOWER ARCH NEEDS SPACE TO RESOLVE CROWDING AND
LINGUAL TIPPING OF MANDIBULAR INCISORS

60.  MANDIBULAR SECOND MOLARS
 FOR SIGNIFICANT DISTALIZATION OF ENTIRE LOWER
DENTAL ARCH
 THE LOWER DENTAL ARCH CAN BE DISTALIZED EITHER
WITH CERVICAL HEADGEAR OR ANCHORAGE DERIVED
FROM INTRORAL IMPLANTS.

61. CONCLUSION
 Early orthopedic treatment using face mask or chin cup
therapy improve skeletal relations which in turn minimizes
excessive dental de compensation.
 Early treatment provides more pleasing facial profile,
thus improves psyco-social development of child.
 It eliminates orthognathic surgery, maximizing growth
potential of maxilla may minimize the extent of surgical
procedures in cases of severe Class III malocclusion.

62. References
 Contemporary orthodontics; william R. profit
 Text of orthodontics, samier bishara
 In clinical orthodontics, Ravindra nanda
 Orthodontics current priciplesand techniques, T.M Graberand
vanarsdal
 DENTOFACIAL ORTHOPEDICS WITH FUNCTIONAL APPLIANCES