Impact of orthodontic treatment on adolescents' quality of life: a longitudinal evaluation of treated and untreated individuals.

Purpose: To assess the impact of fixed appliance therapy on the quality of life of a cohort of Brazilian adolescents.
Methods: The treatment group was composed of individuals who started orthodontic treatment. The control group was composed of individuals not selected for immediate treatment. Adolescents answered the Brazilian short form of the Child Perceptions Questionnaire (CPQ _11-14 ). Higher scores indicate a greater negative impact on quality of life. Adolescents in the treatment group completed four sets of interviews: prior to appliances' bonding (T1), 1 month (T2), 6 months (T3) and 12 months (T4) after appliances' placement. Adolescents in the control group were assigned to a comparable schedule. Statistics included inter-group comparisons, Friedman and Wilcoxon tests, and mixed-effects models.
Results: In the treatment group, the functional limitation score was higher at T1 (p = 0.004) and T2 (p = 0.007) compared to T4. The emotional well-being score was higher at T1 compared to T2 (p < 0.001), T3 (p < 0.001) and T4 (p < 0.001). The overall CPQ _11-14 score was higher at T1 compared to T2 (p = 0.005), T3 (p < 0.001) and T4 (p < 0.001). The overall CPQ _11-14 score was also higher at T2 compared to T3 (p = 0.001). No significant change was found in the control group. In the mixed-effects models, the interaction between group (treatment) and time was significant for functional limitations (p < 0.001), emotional well-being (p < 0.001), social well-being (p = 0.004) and the overall CPQ _11-14 score (p < 0.001).
Conclusion: Quality of life improved among adolescents undergoing orthodontic treatment. Orthodontists should inform patients what they might expect regarding the physical and the psychosocial repercussions of appliance therapy.