The aim of this study was to describe the methodology and results of oral health studies nested in a birth cohort in Pelotas, Southern Brazil. For the oral health studies a sub-sample (n = 900) was selected from the cohort and dental examinations and interviews were performed at ages 15 (n = 888) and 24 years (n = 720; 81.1%). Data collection included dental outcomes, dental care, oral health behaviors, and use of dental services. Mean DMF-T varied from 5.1 (SD = 3.8) to 5.6 (SD = 4.1) in the study period. The proportion of individuals with at least one filled tooth increased from 51.9% to more than 70%. Individuals who had always been poor used dental services less and had fewer healthy teeth on average than those who had never been poor. Individuals with decreasing or increasing family income trajectories showed intermediate values. An increase was seen in the number of healthy teeth from age 15 to 24 only among those who had never been poor. A history of at least one experience with poverty had a negative impact on oral health in adulthood.