Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Access to, and use of, dental health services in Brazil have improved since 2003. The increase of private health care plans and the implementation of the "Smiling Brazil" Program, the largest public oral health care program in the world, could have influenced this increase in access. However, we do not yet know if inequalities in the use of dental health services persist after the improvement in access. The aims of this study are to analyze socioeconomic differences for dental health service use between 2003 and 2008 in Sao Paulo and to examine changes in these associations since the implementation of the Smiling Brazil program in 2003. Method: Data was obtained via two household health surveys (ISA-Capital 2003 and ISA-Capital 2008) which investigated living conditions, lifestyle, health status and use of health care services. Logistic regression was used to analyze associations between socioeconomic factors and dental services use. Additionally, trends from 2003 to 2008 regarding socioeconomic characteristics and dental health service use were explored. Results: Overall, dental health service use increased between 2003 and 2008 and was at both time points more common among those who had higher income, better education, better housing conditions, private health care plans and were Caucasian. Inequalities in use of dental health care did not decrease over time. Among the reasons for not seeking dental care, not having teeth and financial difficulty were more common in lower socioeconomic groups, while thinking it was unnecessary was more common in higher socioeconomic groups. Conclusions: The Brazilian oral health policy is still in a period of expansion and seems to have contributed slightly to increased dental health service use, but has not influenced socioeconomic inequalities in the use of these services. Acquiring deeper knowledge about inequalities in dental health service use will contribute to better understanding of potential barriers to reducing them.16Sao Paulo Research Foundation-FAPESP [2012/214153-0, 2013/26687-2]National Council for Scientific and Technological Development (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)