Angle’s Classification Of Malocclusion

A malocclusion is a misalignment or incorrect relation between the teeth of the two dental arches when they approach each other as the jaws close.

Occlusion when the teeth in the mandibular arch come into contact with those in the maxillary arch in any functional relation, are said to be in occlusion. (Wheeler’s)

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)

WHY TO CLASSIFY?

Grouping of orthodontic problems.
Location of problems to be treated.
Diagnosis & treatment plan. Comparison of different types of malocclusion.
For self-communication. Documentation of problems.
Used for epidemiological studies.
Assessment of treatment effects of orthodontic appliances.

Normal occlusion

Molar Relationship:

According to Angle, the mesiobuccal cusp of the maxillary first molar aligns with the buccal groove of the mandibular first molar.

CLASSIFICATION

Edward Angle, who is considered the father of modern orthodontics, was the first to classify malocclusion
In 1899 Edward H. Angle published classification
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
Classified into 3 classes-class I, class II, class III

Normal occlusion - Normal (Class I) molar relationship, teeth on line of occlusion

Class I malocclusion - Normal (Class I) molar relationship teeth crowded, rotated, etc.

Class II malocclusion -Lower molar distal to upper molar, relationship

Class III malocclusion-Lower molar mesial to upper molar, relationship

Class I malocclusion

Neutrocclusion

A normal molar relationship is present, but there is crowding, misalignment of the teeth, rotations, cross-bites, and other alignment irregularities.

Class II malocclusion

This most commonly causes a retrognathic facial profile.
Distocclusion,
Overjet, overbite
The mesiobuccal cusp of the maxillary first molar occluding anterior to the buccal groove of the mandibular first molar i.e. the maxillary first molar is inline with or anteriorly positioned relative to the mandibular first molar.

The Class II molar relationship can be divided into 2 further parts:

Class II Division 1 – Class II molars with normally inclined or proclined maxillary central incisors
Class II Division 2 – Class II molars with retroclined maxillary central incisors

Class III malocclusion

This causes a prognathic facial profile.
Mesiocclusion,
Anterior crossbite,
Negative overjet, underbite
The mesiobuccal cusp of the upper first molar falls posterior to the buccal groove of the lower first molar.

Advantages of ANGLE classification

First comprehensive classification- most widely accepted
Simple
Easy to use
Most POPULAR
Easy to Communicate

Disadvantages of ANGLE classification

Considers malocculsion only in antroposterior plane not in transeverse/vertical
Considered 1st molar as fixed point – skull
NOT applicable for deciduous dentition
Doesn't distinguish between skeletal and dental malocclusion