Evaluation of the Oral Health-Related Quality of Life (OHRQoL) in Patients Undergoing Lingual Versus Labial Fixed Orthodontic Appliances: A Randomized Controlled Clinical Trial

Background Wearing fixed orthodontic appliances may negatively impact oral health-related quality of life (OHRQoL) during treatment. This study aimed to compare the OHRQoL of patients treated with labial or lingual appliances. Methodology A total of 38 patients (23 females, 15 males; mean age: 21.3 years) with class I malocclusion and moderate crowding in the upper and lower dental arches were included. These patients were planned to be treated on a non-extraction basis and were randomly divided into the following two groups: the lingual appliance (LA) group and the buccal appliance (BA) group. The Oral Health Impact Profile-14 (OHIP-14) questionnaire was used to measure the OHRQoL at the following six assessment times: before treatment (T0), one week after treatment (T1), one month after treatment (T2), three months after treatment (T3), six months after treatment (T4), and at the end of the active treatment (T5). Results In total, 19 patients in each group were included in the final analysis with no dropouts. In both groups, the overall OHIP-14 scores increased and peaked on the first week following appliance placement and then significantly decreased over time. The LA group had significantly greater overall OHIP‑14 scores than the labial group at T1 (p < 0.001) and T2 (p = 0.004) only. Conclusions The OHRQoL improved in both lingual and labial groups after treatment. Moreover, it was better in the labial group compared to the lingual group during the first month of treatment. In both groups, the greatest deterioration in OHRQoL occurred in the first week and gradually decreased over time.