The morphology of the mandibular antegonial notches and facial symmetry

Thirty randomly selected pre-treatment postero-anterior cranial radiographs of adolescent patients attending the orthodontic department, School of Dental Medicine, State University of New York at Buffalo comprised the sample in this study. The aims of this study were (1) to compare the depths of the right, and the left, mandibular antegonial notches, and (2) to determine whether the morphology of the antegonial notches bears a statistical relationship to some other transverse metrical characters of the face. The frontal cranial radiographs of thirty patients were digitized to determine the linear, and surface area, measurements of the right, and the left, antegonial notches as well as some transverse dimensions of the faces. An analysis of variance showed that no statistically significant difference existed between the measurements made by the two examiners, who digitized the radiographs. The data were analyzed by means of the Student’s t- test. The results showed that there were statistically signifi-cant differences (P<0.05) between the measurements of the right, and the left, mandibular antegonial notches. The data also showed that there were highly statistically significant differences between the corresponding bilateral facial dimensions (P<0.001). The results of this study suggest that facial sym-metry, as measured on a frontal skull radiograph, is associated with the respective depths of the right, and the left, mandibular antegonial notches.

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