THE EFFECTIVENESS OF CLASS-II, DIVISION-1 TREATMENT

The aim of this retrospective study was to evaluate the effectiveness of orthodontic treatment in terms of two outcome variables, namely, th e percentage change in a valid and reliable occlusal index, the Peer A ssessment Rating (PAR) score, and the duration of treatment. Data were collected from the records of 250 patients with Class II, Division 1 malocclusions who were treated in the Orthodontic Department of the Un iversity of Pittsburgh between 1977 and 1989. The relationships betwee n the outcome and the treatment variables were analyzed with multiple regression techniques. Those variables significantly associated with t he duration of treatment (p < 0.01) were (1) the pretreatment PAR scor e, (2) the number of treatment stages, (3) the percentage of appointme nts attended, (4) the number of appliance repairs, and (5) whether the patient was treated with or without extractions. The only variable th at influenced the percentage change in PAR was the pretreatment PAR sc ore (p < 0.01).