Cephalometric variables as predictors of Class II treatment outcome

Cephalometric analysis of skeletodental features is accepted as an integral part of orthodontic diagnosis and treatment planning. This assumes that di agnostic cephalometric variables affect prognosis and thus help reduce malo cclusion severity, which is the aim of orthodontic treatment. The aim of th is study was to assess the predictive value of 41 commonly used cephalometr ic parameters with regard to pretreatment severity and treatment outcomes. Pretreatment severity was assessed by using the Peer Assessment Rating (PAR ) occlusal index, an instrument that has been shown to be valid and reliabl e. Treatment outcomes consisted of (I)posttreatment malocclusion severity ( post-PAR), (2) relative improvement (percent PAR reduction), and (3) treatm ent duration. Complete records, including cephalograms, of 223 treated Clas s II cases were analyzed by means of separate multiple linear regression mo dels. Each of the outcome variables and the pretreatment severity served as the respective dependent variables, and the cephalometric parameters serve d as the independent or predictor variables. The cephalometric parameters e xplained 39.2% of the pretreatment severity variance, 17.9% of posttreatmen t severity variance, 15.7% of relative treatment improvement variance, and 20.0% of treatment duration variance.