Abstract: PROPOSE: To compare the changes in oral health-related quality of life(OHRQoL) among adolescent patients and adult patients during orthodontic treatment. METHODS: The clinical data were collected from 81 patients (aged 15 to 25 years old) who underwent comprehensive orthodontic treatment. The participants were divided into 2 groups: adolescent patients (n=43) and adult patients (n=38) by age. OHRQoL was assessed using the Oral Health Impact Profile (OHIP-14). All subjects were examined and interviewed at baseline and the end of 3 stages during orthodontics treatment. Friedman 2-way analysis of variance (ANOVA) and Wilcoxon signed rank tests were used to compare the relative changes of OHRQoL among different time points with SPSS 20.0 software package. RESULTS: The scores of OHIP-14 and all domains except communication disorder and social disability domain in adolescent and adult patients showed significant changes as well as a decrease trend. Only adults showed significant changes in communication disorder.Both groups had no significant difference. CONCLUSIONS: The impact of comprehensive orthodontic treatment on patients' OHRQoL is quite different. Orthodontists should pay attention to the differences and guide the patients accordingly.

Key words: Oral health-related quality of life, Fixed orthodontic treatment, Patient assessment