Seven parameters describing anteroposterior jaw relationships: Postpubertal prediction accuracy and interchangeability

Abstract

Seven parameters describing anteroposterior jaw relationships (the A-B plane angle, the angle of convexity, the ANB angle, the SN-AB angle, the Wits appraisal, the AF-BF distance, the APDI) were measured on pairs of prepubertal and postpubertal cephalograms of 44 normal occlusion subjects (20 males and 24 females). The mean ages at prepubertal and postpubertal stages were 10 years 5 months and 14 years 5 months in males and 8 years 10 months and 12 years 10 months in females, respectively. The purpose of this study was to compare prediction accuracy of future relationships by regression analysis and to evaluate interchangeability among the 7 parameters by correlation analysis. In the prepubertal assessment, the ANB angle and the angle of convexity showed better prediction accuracy for postpubertal jaw relationships. Higher interchangeability among the parameters was statistically substantiated between the SN-AB angle and the AF-BF distance, as well as among the ANB angle, the angle of convexity, and the A-B plane angle. The Wits appraisal and the APDI were less interchangeable with other parameters. The ANB angle, the Wits appraisal, and the APDI would complement each other for the geometrically distorting factors because of the low interchangeability due to their different geometric basis. The conjunctive use of the ANB angle, the Wits appraisal, and the APDI is recommended as a clinically appropriate method for assessment of jaw relationships in individuals. (Am J Orthod Dentofacial Orthop 2000;117:714-20)