Facial growth of skeletal Class III malocclusion and the effects, limitations, and long-term dentofacial adaptations to chincap therapy

Abstract

This article outlines the authors' research findings on the craniofacial growth of untreated skeletal Class III malocclusion, as well as the short-term and long-term effects of chincap orthopedic force for controlling Class III mandibular growth. Skeletal Class III malocclusion is believed to be the result of excessive growth of the mandible with respect to the maxilla and/or cranial base. The results of the authors' longitudinal studies show similar maxillary and mandibular incremental growth change during prepubertal, pubertal, and postpubertal periods when compared with Class I subjects. Therefore, it seems reasonable to assume that the skeletal framework of the Class III malocclusion must have been established before the prepubertal growth period. As for treatment with chincap appliances, the study on short-term and long-term effects indicate that, on average, the skeletal profile is greatly improved during the initial stages of chincap therapy. However, such changes are rarely maintained during pubertal growth period. Treatment with chincap appliances seldom alters the inherited prognathic characteristics of skeletal Class III profiles after completion of growth.