Class II, Division 2 Malocclusions

Class II, Division 2 Malocclusions





Occurs in about 10% of children
In milder forms they may be acceptable functionally, and the facial appearance can be pleasing.
In severe cases the over bite is very deep, associated with periodontal trauma palatal to upper, and labial to the lower incisors.
Class II, Div. 2 incisor relationship is generally the result of dento-alveolar compensation for a class II skeletal pattern by retroclination of the upper central incisors.



Occlusal Features:


Class II incisor relationship with retroclination of the upper central incisors.
The upper lateral incisors may also be retroclined, but typically they are proclined, mesially inclined and mesio-labially rotated
The overbite is deep and over jet is average.
The anterioposterior buccal segment relationship is usually mild class II.
Transversely, there may be buccal crossbite

Skeletal Relationships:


The skeletal pattern may be Class I, but is generally mild Class II, and the chin is well developed so that the facial profile is good.
The lower anterior face height is often smaller than average and characteristically the maxillary-mandibular planes angle is low, with a well-developed mandibular angle.


Facial Growth:


In many class II, Div.2 patients, facial growth is favourable, and there is an anterior mandibular rotation, as might be expected from the diminished anterior face height and the form of the chin.

Soft Tissues:


The lips are almost always of adequate length to meet without strain.
Frequently the lip line is high relative to the upper incisor crown, and the higher the lip line the more retroclined the upper incisors are liable to be. There is often a well-developed labiomental fold.


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