September 2021

Aim: To assess the prevalence of temporomandibular disorder (TMD) in adolescents and estimate possible associations with poverty. Basic research design: A cross-sectional study nested within a prospective birth cohort study conducted in São Luís, Maranhão, Brazil. Participants: 2,412 adolescents aged 18-19 years. Material and Methods: The presence of TMD, classified according to the Fonseca Anamnestic Index, was used as the outcome. The following explanatory variables were assessed: gender, household head, paved/asphalted street, piped water, and socioeconomic background, based on the Brazilian Association of Market Research criteria and the poverty income ratio (PIR). Logistic regression analysis was performed with the estimation of odds ratios (OR) and 95% confidence intervals. Results: TMD was common (51.4%) and was associated with poverty, as it was more frequent among adolescents from social classes D-E (OR=2.60; 95% CI: 1.48-4.55) and C (OR=1.82; 95% CI: 1.12-2.99) compared to A/B, and among poor adolescents using the PIR (OR=1.50; 95% CI: 1.02-2.33). Conclusions: The prevalence of TMD in socioeconomically disadvantaged adolescents in São Luís is high, and these data allow the early identification of at-risk groups. We recommend carrying out other population-based studies, using diagnostic strategies with greater accuracy. Keywords: adolescent, temporomandibular joint disorders, poverty, economic inequality