A cephalometric study of 32 North American black patients with anterior open bite

The purpose of this research project was to investigate a group of 32 North American black patients with anterior open bite and compare them to the North American black norms established by Altemus and Drummond and to white population norms established by Steiner. In addition, values were established for black patients by use of the overbite depth indicator of Kim. The method involved the tracing of lateral cephalometric radiographs of 32 patients with anterior open bite using the analyses of Tweed, Steiner, and Kim. The resulting angles were added and the means and standard deviations calculated. On the basis of the criteria used for this study, the significant findings were as follows: (1) the maxilla was normally positioned to the cranial base; (2) the upper and lower incisors were procumbent with an acute interincisal relationship; (3) the mandibular position tended to be retrusive to the cranial base; (4) the lower facial height was greater and the mandibular plane angle (GoGn-SN) was smaller than white population standards; and (5) the overbite depth indicator of Kim was smaller for this group than for the white population studied.