Classification
of
Malocclusion
Dr. zuber Ahamed Naqvi
Objectives
•
•
•
•
•
•
•
•
Definition
Intra arch malocclusion
Angle’s classification of malocclusion.
Lischer and Dewey’s modification of angle’s
classification of malocclusion.
Skeletal classification.
Incisor classification.
Canine classification.
Simon’s classification.
MALOCCLUSION..
A CONDITION IN WHICH THERE IS A DEFLECTION
FROM THE NORMAL RELATION OF THE TEETH TO
OTHER TEETH IN THE SAME ARCH AND/OR TO TEETH
IN THE OPPOSING ARCH.
(GARDINER, WHITE& LEIGHTON)
Malocclusion
Intra arch malocclusion
Intra arch malocclusion
mesial inclination or mesial tipping
Distal inclination or distal tipping
Buccal inclination or buccal tipping
lingual inclination or lingual tipping
Inter arch malocclusion
mesial displacement
Distal displacement
lingual displacement
buccal displacement
intrusion
extrusion
Disto lingual rotation
mesio lingual rotation
transposition
Vertical relationship between central incisors
Normal
Deep bite
Open bite
Angle’s classification of malocclusion
The classifications are based on the
relationship of the mesiobuccal cusp of the
maxillary first molar and the buccal groove of
the mandibular first molar.
Line of occlusion- the line of occlusion is a
smooth ( caternary) curve passing through the
central fossa of each upper molar and across
the cingulum of the upper canine and incisor
teeth.
The same line runs along the buccal cusps and
incisal edges of the lower teeth, thus specifying
the occlusal as well as interarch relationships
once the molar position is established.
Class I malocclusion
The mesiobuccal cusp of
the upper first permanent
molar occludes with the
mesiobuccal groove of the
lower first molar, but line
of occlusion is incorrect
because of malposed teeth,
rotations or other
discrepancies.
Angle’s class II malocclusion
The mesiobuccal cusp of the
upper first permanent molar
occludes mesial to the
buccal groove of mandibular
first molar.
Angle’s class II division 1
malocclusionClass II molar relationship is
present with proclined upper
central incisors.
There is an increase in
overjet.
Angle’s class II division 2 malocclusionClass II molar relationship is
with retroclined upper
central incisors, Upper
lateral incisors may be
proclined or normally
inclined.
•Overjet is usually minimal
or may be increased.
CLASS II SUB-DIVISIONCondition when the class II
molar relationship exists on
only one side with normal
molar relationship on the
other side.
CLASS II MALOCCLUSION
Division 1
Division 2
Overjet
Increased
decreased
Profile
Convex
Straight or mild convex
Lips
Short, incompetent
Competent
Arch form
V shaped, narrow
U shaped or square
Palate
Deep
Normal depth
Muscle activity
Increased mentalis or
buccinator
Normal muscle activity
Path of closure
Normal
Backward
Lower facial height
Normal or incresed
Decreased
Malar process
Not prominent
Prominent
Class III malocclusion
The mesiobuccal cusp of the upper fist
molar occludes distal to the buccal
groove of lower first molar .
PSEUDO CLASS III
Malocclusion due to occlusal
prematurity.
It’s also known as postural class III.
• CLASS III SUB-DIVISION –
• class III molar relationship is present
only on one side with class I relation
on the other side.
MODIFICATIONS OF ANGLE’S CLASSIFICATION
•
•
•
•
•
•
•
•
•
•
•
•
•
•
1.Lischer’s modification.
2.Dewey’s modification.
LISCHER’S MODIFICATION
He introduced following names to the Angle’s classification(mandibular
molar):–
Neutrocclusion- Class I.
Distocclusion- Class II.
Mesiocclusion- Class III
DEWEY’S MODIFICATION
Martin Dewey divided Angle’s class I & III into further types:–
CLASS I:-----Type 1: Crowded maxillary anterior teeth. Canines may be abnormally
positioned.
Type 2: Proclined or labioversion of maxillary incisors.
Type 3: Anterior cross bite present.•
Type 4: Posterior cross bite present.•
Type 5: Mesioversion of molars.
DEWEY’S MODIFICATION
CLASS III
Type 1: Well aligned teeth & dental arches.
Edge-edge relationship.
Type 2: Crowded mandibular incisors and are in
lingual relation to the maxillary incisors.
Type 3: Crowded maxillary incisors,
underdeveloped maxilla.
Anterior cross bite present.
SKELETAL CLASSIFICATION
•
Relationship between maxilla &
mandible, in anteroposterior direction.
•
Skeletal CLASS I: Maxilla & mandible
are in harmony with each other.
•
Skeletal CLASS II: Maxilla lies ahead
of mandible with refrence to anteroir
cranial base. Maxilla is prgnathic.
•
Skeletal CLASS III: Maxilla lies
posterior to mandible with reference to
anterior cranial base.
In other words maxilla is retrognathic.
•
BRITISH STANDARD CLASSIFICATION OF INCISOR
RELATIONSHIP (1983)
•
Based upon incisor relationship, proposed in
1983. (Do not consider molar relationship in
some cases.)
•
CLASS I: The lower incisor edges occlude
with or lie immediately below the cingulum
plateau of upper central incisors.
CLASS II: The lower incisor edges lie
posterior to the cingulum plateau of the upper
incisors. There are two sub-divisions:–
DIVISION 1: The upper central incisors are
proclined or of average inclination & there is
an increase in overjet.–
DIVISION 2: The upper central incisors are
retroclined. The overjet is usually minimal or
may be increased.
CLASS III: The lower incisor edges lies
anterior to the cingulum plateau of the upper
incisors. The overjet is reduced or reversed.
•
•
•
CANINE CLASSIFICATION
•
CLASS I : When the mesial slope of
upper canine coincides with the distal
slope of lower canine.
•
CLASS II : When the mesial slope of
upper canine is ahead of the distal
slope of lower canine.
•
Class III : When the mesial slope of
the upper canine lies behind the distal
slope of the lower canine.
SIMON’S CLASSIFICATION
•
•
•
In Simon’s classification system,
the dental arches are related to
three anthropologic planes.
PLANES USED:–
Frankfort horizontal plane
Orbital plane
Mid-saggital plane.
FRANKFORT HORIZONTAL
PLANE:-Helps detect deviations
in the vertical plane.-Dental arch
closer to the plane is called
attraction and farther away is
called abstraction.
SIMON’S CLASSIFICATION
ORBITAL PLANE:-Dental arch
more anteriorly placed is called
protraction and posteriorly
placed dental arch is called
retraction.
MID-SAGGITAL PLANE:Dental arch closer to
midsaggital plane is called
contraction and farther away
is called distraction.
Ackerman Profitt system of classification
References
.
William R. Proffit,Contemporary orthodontics; 4th edition