A predictive model of ''favorable'' and ''unfavorable'' anteroposterior skeletal relations among Class Is and Class IIs

Abstract

Objectives: To validate the use of the sagittal distance between ANS and Pg (ANSPg) as a measure of favorable and unfavorable anteroposterior skeletal relations and to identify multivariate cephalometric measures that could be used to predict favorable and unfavorable relations at 15 years of age. Materials and Methods: This longitudinal study included 226 untreated adolescents evaluated at 10 and 15 years of age. Patients were grouped as ''favorable'' or ''unfavorable'' based on the ANSPg (measured parallel to S-N -7°) at 15 years of age (ANSPg15). ANSPg15 was validated based on its correlation with changes in ANSPg between 10 and 15 years of age, as well as its relationships with established measures of growth potential. Multiple regression and discriminant analyses were performed to predict ANSPg15 from measures at 10 years of age. Results: ANSPg15 and the change in ANSPg between 10 and 15 years of age were significantly correlated (R= -0.661; P ≤.001), with 77% of patients in whom relationships improved (ie, distance decreased) exhibiting favorable relationships at 15 years of age. Established measures of growth potential were significantly (P