Document Type : Research Article
Abstract
Edward H. Angle described III class of bite anomalies where the lower first molar is
located mesially relative to the upper first molar [4,7]. This ratio may be the result of the normal location
of the upper jaw and mesial skeletal location of the lower jaw or develop due to a combination of the
upper jaw in retrusion and the lower jaw in protrusion. Dental relations of class III are found in persons
with normal jaw relations [1,3,6]. Patients with class III anomalies usually have a concave facial profile,
their lower lip often protrudes concerning the upper lip. Sometimes, the class III anomaly ratios are
formed by shifting the lower jaw forward to avoid incision. This is a false form of class III anomalies.
Undoubtedly, the etiological factors of class III bite disorder and oral cavity functions are influenced by
environmental factors, but the causes of this phenomenon are not fully known (] [1,2,5,8].