Retrospective evaluation of the outcome of orthodontic treatment in adults

Abstract

The aim of this study was the retrospective evaluation of the outcome of orthodontic treatment in consecutively treated adult patients. Of 147 adult patients, it was possible to evaluate the records of 88 patients (57 female, 31 male) before (T1) and after treatment (T2), and of 20 of these patients 3.3 years on average after completion of the retention phase (T3). During treatment planning, a nearly "ideal" result was considered attainable (ideal group) for 46 patients, and a "compromise" result (compromise group) was seen as realistic for 42. The assessment was made using the PAR (Peer Assessment Rating) index and the Aesthetic Component (AC) and Dental Health Components (DHC) of the IOTN (Index of Orthodontic Treatment Need). Average length of treatment in the ideal group was 2.4 years, i.e. nearly twice as long as in the compromise group. The PAR score was reduced by an average of 56% (T2); the reduction in the ideal group was 73%, and in the compromise group 37%. Among the 20 patients for whom at least 6 months had elapsed since completion of the retention phase, a statistically significant relapse between T2 and T3 was observed. The evaluation of overjet and overbite and, in the ideal group, of the midline and maxillary front teeth were primarily responsible for the worsening of the PAR scores between T2 and T3. According to the AC, 53 patients (60%) had moderate to definite treatment needs at the beginning of treatment. Following completion of active treatment, 69 patients (78%) no longer demonstrated treatment indications for aesthetic or psychosocial reasons. Based on the DHC, 88% of the patients were in definite or moderate need of treatment (T1); in contrast, treatment was no longer indicated in 84% at T2. In general, a marked improvement of the examined morphological parameters was observed.