OBJECTIVES: In light of the growing interest in orthodontic care and its effectiveness in Germany, part 2 of this multicenter cohort study evaluated patient-reported outcomes such as oral health-related quality of life (OHRQoL), oral hygiene habits, oral health beliefs, and potential influencing factors.

METHODS: Of 586 patients screened from seven German study centers, data from 343 patients were analyzed for this part of the study. At the end of their orthodontic treatment, study participants filled out a questionnaire of either the German long version of the Oral Health Impact Profile (OHIP-G 49) or the German short version of the Child Oral Health Impact Profile (COHIP-19), depending on their age, as well as questions about their oral hygiene behavior and beliefs. Patient-, treatment- and occlusion-related factors were analyzed to account for potential influencing factors with regard to patients' OHRQoL after orthodontic treatment.

RESULTS: In all, 222 study participants filled out the OHIP-based and 121 the COHIP-based questionnaire. The mean OHIP-G 49 score was 12.68 and the mean OHIP-G 14 score was 3.09; the mean COHIP-19 score was 6.52 (inverted score 69.48). For OHIP-G 49 scores, a nonsignificant trend towards a higher score for male patients (14.45 vs 11.54; p = 0.061) was detected, while this trend was inverse for the COHIP-19 scores, i.e., female patients reported more impairment (total score 6.99 vs. 5.84; p = 0.099). Analyses suggested a trend towards better OHRQoL for patients who classified for the Peer Assessment Rating (PAR) Index improvement rate group 'greatly improved' as well as for nonsmokers. Oral hygiene habits and beliefs after orthodontic treatment were estimated to be good.

CONCLUSION: In this German cohort, OHRQoL proved to be good and was rather unimpaired after orthodontic treatment. Furthermore, self-reported oral hygiene behavior and oral health beliefs represented good health awareness.