The vertical dimensions of the face and skeletodental retrognathism

Abstract

This study deals with nine vertical dimensions in skeletodental retrognathism. Twenty-five boys and twenty-five girls, 11 years of age, with Class II molar relationships and ANB angles of 4.5 degrees or greater, were compared with twelve girls and thirteen boys, 11 years of age, with Class I molar relationships and ANB angles of less than 4.5 degrees.The vertical dimensions used were found to be significantly larger in the boys than in the girls. The vertical position of the mandible and palatal portion of the maxilla was not found to be different in retrognathism, but there appeared to be a slight tendency for the maxillary dentoalveolar height to be greater in retrognathism than in orthognathism. On the other hand, in these samples, there was no difference between retrognathism and orthognathism in anteroposterior position of the maxillary dentition relative to sella. A significant difference was found between samples for both sexes in the mandible, which was found to be smaller and more posteriorly positioned in retrognathism than in orthognathism. It was observed that the mandibular plane angle is slightly larger in retrognathism than orthognathism. However, the size of the mandibular plane angle appears to be related only slightly to the severity of the retrognathism.