Buto & Alter Orthodontics
Orthodontics
Oxnard, CA, Thousand Oaks, CA
805-485-5150

TREATMENT INFO

Teeth and Face Classifications

The classification of tooth and jaw relations is divided into three main categories: Class I, II, and III. This classification system refers to the position of the upper and lower first molars and how they relate to one another. The bite, or occlusion, may be better understood in this way.

Class I

Class I is a normal relationship between the upper and lower teeth and jaws, or a balanced bite.

Class II

Class II malocclusion is described as the lower first molar being more posteriorly (or more towards the back of the mouth) positioned relative to the upper first molar. In this abnormal relationship, the upper front teeth and jaw project further forward than the lower teeth and jaw. There is usually a convex appearance in profile resulting from the recessive lower jaw and chin. This is commonly referred to as an "overbite." Class II malocclusions can be due to insufficient growth of the lower jaw (the mandible), an overgrowth of the upper jaw (the maxilla), or a combination of the two. In many cases, Class II deficiencies are genetically inherited and can be aggravated by environmental factors such as digit sucking (finger or thumb sucking). Class II malocclusions are treated via growth modification, thereby redirecting the upper and lower teeth and jaws into a more balanced, harmonious relationship.

Class III

Class III malocclusion is described as the lower first molar being more anteriorly (or more towards the front of the mouth) positioned relative to the upper first molar. In this abnormal relationship, the lower teeth and jaw project further forward than the upper teeth and jaw. There is usually a concave appearance in profile with a prominent chin. This is commonly referred to as an "underbite." Class III malocclusions are usually due to an overgrowth in the lower jaw (the mandible), an undergrowth of the upper jaw (the maxilla) and midface, or a combination of the two. Like Class II malocclusions, they can be genetically inherited.