The aim of this study was to identify the risk factors for tooth loss in an extended age group of adults over 4 years. The prospective cohort study assessed adults (20-64 years old) in 2011 and 2015, from Piracicaba, São Paulo, Brazil. The sample selection was planned based on the adult population in the city. The inclusion criteria were randomly selected residences per census tract unit (one adult per household). The exclusion criteria comprised of a physical or psychological state that prevented the achievement of clinical procedures or understanding of the questionnaire. The home oral examination was performed using the index of decayed, missing, and filled teeth (DMFT), the Community Periodontal Index according to the World Health Organization, and visible biofilm. Demographic and socio-economic data, information on health habits, and the use of dental services were obtained by questionnaire. The outcome was a presence incidence of tooth loss, assessed by the difference between Missing teeth (M>0) from DMFT in 2011 and that in 2015. The conceptual theoretical model 'Ethnicity, aging and oral health outcomes' was adapted for tooth loss and used in a Hierarchical multivariate Poisson Regression analysis (p<0.20). The reference category for the Poisson regression were individuals who had no missing teeth (M) due to caries or periodontal disease (p<0.05). There were a total of 143 (follow-up rate = 57.7%) participants in the four-year study, and there was incidence of tooth loss in 51 (35.7%) adults over this period. The risk factors for tooth loss were reason for seeking dental services by pain (RR = 2.72; 95.0% CI: 1.04-7.37), previous tooth loss (RR = 3.01; 95.0% CI: 1.18-7.73) and decayed teeth (RR = 2.87; 95.0% CI: 1.22-6.73). The risk factors for tooth loss were: reason for seeking dental services by pain, previous tooth loss and dental caries.