Abstract
The results of 264 consecutively treated orthodontic cases were evaluated. According to the defined criteria, optimal treatment objectives were only achieved in 43.2% of the cases. Some of the treatment problems and reasons for failure are identified and discussed. In 16% of cases co-operation problems were the main obstacle to successful treatment. Significant root resorption was observed in 14% of cases. The overall probability for elimination of increased overjet was found to be 71%. Myo-functional problems were an obstacle to treatment in several cases. 1.8% of patients were dissatisfied with the treatment result for aesthetic reasons. It is concluded that close study of treatment problems and failures must be undertaken on an individual basis but ‘failure rate’ or ‘score of success’ should be taken into consideration more frequently in clinical orthodontics.