The depth of the mandibular antegonial notch as an indicator of mandibular growth potential.

The craniofacial characteristics and growth potential of 25 orthodontically treated patients with deep mandibular antegonial notch were compared with a similar group of 25 shallow notch subjects by the use of longitudinal lateral cephalometric radiographs. Deep notch cases had more retrusive mandibles with a shorter corpus, smaller ramus height, and a greater gonial angle than did shallow notch cases. The lower facial height in the subjects with a deep mandibular notch was found to be longer, and both the mandibular plane angle and facial axis were more vertically directed. During the average 4-year period examined, the deep notch sample experienced less mandibular growth as evidenced by a smaller increase in total mandibular length, corpus length, and less displacement of the chin in a horizontal direction than did the shallow notch sample. The results of this study suggest that the clinical presence of a deep mandibular antegonial notch is indicative of a diminished mandibular growth potential and a vertically directed mandibular growth pattern.