Introduction Dental appearance comprises an important aspect of oral health. However, no study has investigated the dynamics of dissatisfaction with dental appearance and other aspects of oral health using a birth cohort study.

Objectives This study estimated the prevalence of dissatisfaction with the dental appearance among 24-yr-old Brazilian adults and the association with potential life course risk factors. A cross-sectional study nested in a birth cohort study was carried out in Pelotas, Brazil. A representative sample (n=720) of all 5914 births occurring in Pelotas in 1982 was prospectively investigated and the outcome was assessed in 2006. Exploratory variables were collected at birth, at 15 and 24 yr of age and included demographic/socioeconomic, oral health, appearance satisfaction and use of dental services. Dissatisfaction with dental appearance at aged 24 yr was the outcome. Unadjusted and adjusted multivariable Poisson regression was performed followed a theoretical model.

Results The prevalence of the outcome was 43.5% (39.8;47.2). In the final model, low socio-economic status through the life-course [RR 1.21 (95% CI 1.00 to 1.57)], malocclusion at aged 15 yr [RR 1.34 (1.13 to 1.59)], dental pain at aged 24 yr [RR 1.29 (1.08 to 1.55)], adolescent's dissatisfaction with appearance [RR 1.20 (1.01 to 1.43)], and untreated dental caries at aged 24 (highest tertile) [RR 1.82 (1.46 to 2.27)] were associated with dental appearance dissatisfaction.

Conclusion Our findings showed that the individuals with dissatisfaction with their physical appearance at age 15 were more likely to rate their oral health as worse than their counterparts. Participants with downwardly income trajectory had the worst dissatisfaction with the dental appearance.