March 2022

Objective: To determine the sociodemographic and clinical factors that may influence oral health-related quality of life (OHRQoL) at ages 12 to 15. Basic research design: Cohort study. Participants: Cluster-randomized sample of Hong Kong 12-year-olds. Main outcome measures: The Child Perceptions Questionnaire (CPQ11-14) was used to measure OHRQoL as the response variable. Periodontal status and caries were examined according to WHO criteria. Malocclusion was assessed using Dental Aesthetic Index. Potential predictors of OHRQoL (age, gender, father’s education, mother’s education, household income, periodontal status, caries, and malocclusion) were analyzed by structural equation modelling. Results: At age 12, 589 participants (305 females, 284 males) were included. At age 15, 331 (172 females and 159 males) were followed up. For direct effects, age 15 was associated with higher oral symptoms (OS) scores (β=0.124, 95%CI=0.049 to 0.2) but lower emotional well-being (EWB) scores (β=-0.105, 95%CI=-0.184 to -0.03). Males had higher OS scores than females (β=0.126, 95%CI=0.059 to 0.208). Mother’s education had positive effects on children’s EWB (β=-0.096, 95%CI=-0.159 to -0.018). Malocclusion had negative effects on functional limitations (FL) (β=0.083, 95%CI=0.013 to 0.186). For indirect effect, mother’s education showed a link via EWB to OHRQoL (β=-0.077, 95%CI=-0.123 to -0.018). Malocclusion showed a link via FL to OHRQoL (β=0.037, 95%CI=0.006 to 0.087). Conclusions: Age, gender, mother’s education and malocclusion predicted OHRQoL at ages 12 and 15. Keywords: adolescents, oral health-related quality of life