classification of malocclusion

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CLASSIFICATION OF MALOCCLUSION

Presented by,

Dr. Bibin Ninan Mathew

SYNOPSIS INTRODUCTION

DEFINITIONS: OCCLUSION

IDEAL OCCULSION NORMAL OCCLUSION MALOCCLUSION

HISTORICAL REVIEW

NEED OF CLASSIFICATION

TYPES OF MALOCCLUSION

VARIOUS SYSTEMS OF MALOCCLUSION

NEWLY PROPOSED CLASSIFICATION

CONCULSION

INTRODUCTION

In the specialty of orthodontics, the classificationof malocclusion plays several very importantroles. classification aids in the diagnosis and treatment planning of malocclusions by orienting the clinician to the type and the magnitude of the problems and possible mechanical solutions to the problems…

OCCLUSION

oc clusion

CLOSINGUP

CLOSING UP

MALOCCLUSION

MAL OCCLUSION

BITEBAD

BAD BITE

OCCULSIONIDEAL OCCLUSION

NORMAL OCCLUSIONMALOCCLUSION

The relation of theMaxillary and Mandibularteeth when the jaws are

- Closed in centricrelation

- Without strain ofmusculature ordisplacement ofcondyles in theirfossae

OCCLUSIONDEFINITION

IDEAL & NORMAL OCCLUSION

“IDEAL” is a hypothetical concept ora standardized goal

“Normal” implies to the variationsaround an average mean value

The Perfect Occlusion

It is a theoretical concept based on the ideal teeth position and arches relationships. It is rarely, , if ever, found in nature. However, it provides a standard

by which all other occlusions may be judged.

• A coincident mid-line• No (crowding/spacing/rotations)• Over-jet = 2-3mm• Correct crown angulation and inclination• Class I molar & canine relationship• A flat or slightly upwards curve of Spee

Ideal occlusion Normal occlusion

- Is one which shows:some deviation from that of the idealbut is aesthetically acceptable andfunctionally stable for the individual

- the upper and lower teeth fit nicelyand evenly together with the leastamount of destructive interferences

Andrews 6 KEYS of Normal Occlusion(1972)

Correct crown inclination

No spaces Flat to slight curve of spee

No rotation

Correct crown angulationClass I molar relationship

Definition:

Malocclusion may be defined as―A condition where there isdeparture from the normal relationof the teeth to

- other teeth in the same dental archand/or to

- teeth in the opposing arch

The term was coined by Edward H Angle, the "father of modern orthodontics“.

MALOCCLUSION

It is a condition that reflects an expression of

normal biologic variability in the way the maxilla

and mandible teeth occlude (BISHARA)

An occlusion In which there is a malrelationship

between the arches in any of the planes of the spaces

or in which there are anomalies in tooth position

beyond the limit of normal. (Walther & Huston)

Occlusion and malocclusion

HISTORICAL REVIEW

( 1829) Samuel S Fitch - described in his book‘ A System of Dental Surgery’ first classified into 4 states of irregularity.

(1836) Christopher kneisel - ‘The oblique position of teeth’- classified –general obliqueness & paritial obliqueness.

(1839) Jean Nicolas Marjolin - differentiated obliqueness of teeth and anomalies of dental arch.

(1842) George Carabelli - coined the term edge-to-edge bite and overbite.

Classification was based on the positions of incisors and canines which has termed as:

Mordex Normalis : Normal occulsionMordex rectus : Edge to edgeMordex apertus : Open occlusionMordex prorsus : protruding occlusionMordex retrous : Retruding occlusionMordex tortuosus : Zig –zag occlusion

(1880) Norman Kingsely – classified into 2 broad categories based on etiology

Developmental malocclusion Accidental malocclusion Edward H Angle ( 1899, 1900, 1906.1907) – detailed

description of malocclusion into 3classes

(1912) Lischer– terms distocclusion and

mesiocclusion

(1915) Martin Dewey–modified Angles classes

(1920) Paul Simon-based on the gnathostatics and

canine law

(1964) Ballard and Wayman- British classification

based on incisor overjet

(1969) Ackerman and proffit - based on venn diagram

(1992) Katz- based on premolar as a reference

landmark

(1905-1921)- Calvin case -anatomical groups- grouped

into 5 classes- treatment standpoint of view

The World Health Organization (1987), had included

malocclusion under the heading of Handicapping Dento

Facial Anomaly, defined as an anomaly which causes

disfigurement or which impedes function, and requiring

treatment “if the disfigurement or functional defect was

likely to be an obstacle to the patient’s physical or

emotional well-being”

What is a classification system ??

A classification system is a grouping of clinical cases of similar appearance for ease in handling and discussion; it is not a system of diagnosis , method for determining prognosis ,or a way of defining treatment

Robert E.Moyers

Why we need a Classification for malocclusion ???

Acquire a better understanding of the many

deviations from normal occlusion

1) divide the wide range into small groups.

2) describe the salient features.

3) provide a verbal and mental picture.

4) simplify the documentations

5) unify the communications.

7) give clue about the etiology.

8) help to select treatment modality.

Thinking of possible treatment modalities that may

be needed in a particular case

TYPES OF MALOCCULSION

INTER ARCH

SKELETAL

INTRA ARCH

INTRA ARCH

Includes variation in individual tooth position & a group of teeth within in a arch

Abnormal inclination

Abnormal Displacements

Spacing and crowding within the same

arch

Distal inclination Mesial inclination

Buccal inclination

Lingual inclination

ABNORMAL INCLINATION

Labioversion

Lingoversion

ABNORMAL DISPLACEMENTS

Palatoversion

Buccoversion

Supraversion

Infraversion

Torsiversion

Types

INTERARCH PROBLEMS

Abnormal relationship between two teeth or group of teeth of one arch to the other

Sagittal plane malocclusions

Vertical plane malocclusions

Transverse plane malocclusions

SAGITTAL DIRECTION

Either :

- Abnormal overjet- Anterior cross-bite

Anteriorly

Class II malocclusionClass III malocclusion

Posteriorly

OR

Vertical plane malocclusions

Normal overbite

Deep overbite Open bite

Transverse plane malocclusions

Either :

DEVIATIONS OF THE MIDLINEAnteriorly

POSTERIOR CROSS BITE: Posteriorly

OR

Skeletal malocclusions

Malrelation of the apical bases:

Malrelation of the upper and lower apical bases is due to:

a. Abnormal size;

b. Abnormal shape;

c. Abnormal relation to the

skull;

d. Abnormal relation to

each other.

VARIOUS SYSTEMS OF CLASSIFICATION

ANGLE CLASSIFICATION

DEWEY’S MODIFICATION OF ANGLES

CLASSIFICATION

LISCHER’S MODIFICATION OF ANGLES

CLASSIFICATION

SIMONS SYSTEM

BENNET’ S CLASSIFICATION

ACKERMANN AND PROFITT CLASSIFICATION

BALLARDS CLASSIFICATION

PREMOLAR CLASSFICATION

NEWLY PROPOSED SYSTEM

ANGLE CLASSIFICATION

It was introduced by Edward H. Angle (1889)

• Based on the mesiodistal relationship of teeth, dental arches and jaws

• Maxillary first molar is taken as the key of occlusion

• Three classes

Class I

Class IIClass II div 1Class II div 2Class II SubdivisionClass II division 1

SubdivisionClass II division 2 Subdivision

Class IIITrue Class IIIPseudo Class III

THREE CLASSES

Class III Subdivision

NORMAL LINE OF OCCLUSION

Angle Class І malocclusion Neutroclusion

Molar relationship

Canine relationship

-

Line of occlusion: ALTERED in the max. & mand. Arches:

• individual tooth irregularities (crowding/spacing/….)

• Inter-arch problems (deep bite/open bite/ increased overjet/…)

Angle Class ІІ malocclusion

Canine relationship:- the distal incline of upper canine anterior to the mesial incline of lower first premolar

DistoclusionMolar relationship:

There are two divisions of class ІІ designated, division 1 and division 2

Angle Class ІІ malocclusion division 1

Angle Class ІІ malocclusion division 2

Angle Class ІІ malocclusion division I

Class ІІ Division 1 : -Mandible is retruded and- all maxillary incisors are protruded

Angle Class ІІ malocclusion division II

Mandible is retruded and one or more maxillary incisors are

retruded

Class ІІ Division 2 :

class I molar

class ІІ molar

Class ІІ malocclusion

subdivision

Angle Class ІІI malocclusion

True class III

Genetic in origin Excessively large mandible Smaller than normal maxilla Retropositioned maxilla

Class ІІІ malocclusion: 2 types

- True class ІІІ malocclusion (Skeletal)- Pseudo class ІІІ (FALSE or postural)

Pseudo class ІІІ

Forward movement of mandible during jaw closure Occlusal prematurities Premature loss of deciduous posteriors Enlarged adenoids

Advantages of ANGLE classification

First comprehensive classification- most widely

accepted

Simple

Easy to use

Most POPULAR

Easy to Communicate

DEMERTIS OF ANGLE CLASSIFICATION

Considers malocculsion only in antroposterior plane

not in transeverse/vertical

Considered 1st molar as fixed point – skull

Deciduous dentition

1st molar extracted

Doesn't distinguish between skeletal and dental malocclusion

Doesn’t highlight etiology

Individual tooth positions

DEWEY’S MODIFICATION OF ANGLES MALOCCLUSION (1915)

Divided angles class I into five types and angles class III into three types

Class I modification of Dewey

Class III modification of Dewey

Type 1 : Class I malocclusuion with bunched or crowded anterior teeth

Type 2: class I with protrusive maxillary incisors

Type 3: Class I malocclusion with anterior crossbite

Type 4: Class I malocclusion with posterior crossbite

Type 5: the permanent molar has drifted mesially due early extraction of second deciduous molar or second premolar

Class III modification of Dewey

Type 1:Upper and lower arches are normally aligned separetely but show edge incisor bite

Type 2: the mandibular incisors are crowded and lingual to the maxillary incisors

Type 3: maxillary incsiors are crowded and in crossbite with mandibular anteriors

Lischer’s modification (1933)

Neutrocclusion : Angles class I malocclusion

Distocclusion : Angles class II malocclsion

Mesioclusion : Angles class III malocclsion

Buccocclusion : Buccal placement of a tooth or a group of teethLinguocclusion : lingual placement of a tooth or a group of a tooth or a group of teeth

Supraocclusion : when a tooth or group of teeth have erupted beyound normal levelInfraocclsion : when a tooth or group of teeth have not erupted to normal level

Mesioversion : mesial to the normal positionDistoversion : distal to the normal position

Transversion : transposition of two teethAxiversion : Abnormal axial inclination of a toothTorsiversion : Rotation of a tooth around its long axis

BENNET’S CLASSIFICATION

Based on ETIOLOGY

CLASS I- Abnormal position of one or more teeth due to

local causes

CLASS II- Abnormal formation of a part or a whole of

either arch due to developmental defects of bone

CLASS III- Abnormal relationship between upper and

lower arches, and between either arch and facial contour

and correlated abnormal formation of either arch

SIMONS CLASSIFICATION (1926)

It is craniometric classification

Based on abnormal deviations of dental arches from their normal position in relation to these 3 planes

VERTICAL PLANE

ANTERO-POSRTERIOR

TRANSVERSE PLANE

‘ GNATHODYNAMOMETER ’

ATTRACTION ABSTRACTION

FH PLANE

This plane help to detect devotions in the VERTICAL DIRECTION

ORBITAL PLANE

Perpendicular to the FHP

Simon’s law of canine- “thisplane should pass throughthe distal third of the canine”

This plane used to describe malocclusion in ANTERIO-POSTERIOR direction

Protraction

Retraction

THIS plane passes at right angle to FHP

MID SAGITTAL PLANE

It classifies malocclusion according to TRANSVERSE DEVIATION from MSP

CONTRACTION

DISTRACTION

ACKERMAN-PROFIT SYSTEM ( 1960 )

Based on five characteristics

o ALIGNMENTo PROFILEo TRANSVERSE RELATIONSHIPo CLASSo BITE DEPTH

Transverse & vertical discrepancies –considered

Crowding and arch asymmetry -evaluated

Incisor protrusion

Influence of dentition on the profile

Features…

BALLARDS CLASSIFICATION

Incisor classification (1965)

A classification of malocclusion based on incisor

As treatment is often primarily aimed at correcting this relationship

Three CLASSES

Class I incisorClass II incisorClass III incisor

Class I incisor

Class II incisor

Div 1

Class III incisor

KATZ PREMOLAR CLASSIFICATION (1992)

PREMOLAR CLASS I - most anterior upper premolar fits exactly into the embrasure created by the distal contact of the most anterior lower premolar represent prefect interdigitations , the value – 0 mm

Premolar class II- the most anterior upper premolar is occluding mesial of the embrasure created by the distal contact of the most anterior lower premolar ( )

5 4 3

5 4 3

PREMOLAR CLASS III- the most anterior upper premolar is occluding distal of the embrasure created by the distal contact of the most anterior lower premolar. The meaurement has a(-) sign

Advantages

This system provides a quantitive treatment objective that is needed to attain excellent buccal occlusion

It provides some flexibility in terms of finishing a case in functional class II or class III buccal occlusion ,while keeping buccal interdigitation as the prime goal

In deciduous and mixed dentition cases, emphasis is shifted from the permanent first molars to the region of current importance i.e. deciduous molar region

Disadvantages

Premolars, are commonly missing, malformed or supernumerary , hence measurement is not always possible

Severely rotated and ectopically erupted premolars problems

No consideration for the facial balance and aesthetics

NEWLY PROPOSED SYSTEMFOR MALOCCLUSION CLASSIFICATION (MIGUEL-NETO & MUCHA) (2010)

MIGUEL-NETO, A. B.; NISHIO, C. & MUCHA, J. N. Agreement evaluation of a newly proposed system for malocclusion classification. Int. J. Odontostomat., 4(1):33-41, 2010.

CLASS I

CLASS II

CLASS III

CLASS I

CLASS II

CONCLUSION

AS ORTHODONTISTS A GOOD KNOWLEDGE OF DIFFERENT SYSTEMS OF CLASSIFICATIONS OF MALOCCLUSION,IT’S MERITS AND DEMERITS IS VERY IMPORTANT IN MAKING PROPER DIAGNOSIS AND EFFECTIVE TREATMENT PLANNING..

References Contemporary Orthodontics,-William R. Profitt, 3rd edition

Grabers Textbook of Orthodontics Basic principles and practice- 4th edition

Handbook of Orthodontics 4th edition- Robert E. Moyres

Textbook of Orthodontics , Samir E.Bishara

Orthodontics, Current principles and Techniques, 4th edition, Graber Vanarsdal

Classification of Malocclusion, Edward H.Angle,The Dental Cosmos

The six keys to normal occlusion, Lawrence F. Andrews, D.D.S. Am. J. Orthod. September 1972, vol 62 number-3

Angle classification revisited 1: Is current use reliable? Morton I. Katz, DDS"Washington,D.C.

A matter of Class: Interpreting subdivision in a malocclusion . Molly A. Siegel, DDS,Am J Orthod Dentofacial Orthop 2002;122:582-6)

Agreement Evaluation of a Newly Proposed System for Malocclusion Classification

Miguel-neto, A. B.; Nishio, C. & Mucha, J. N. Int. J. Odontostomat., 4(1):33-41, 2010.

Thank you

BIBINS PHOTOGRAPHY