Objective: To analyse trends in dental pain prevalence among Brazilian adolescent students over 6 years, focusing on inequalities by maternal education. Methods: Data from the National Adolescent School-Based Health Survey (PeNSE) carried out in 2009 (n = 45 239), 2012 (n = 46 482) and 2015 (n = 35 592) were analysed, including ninth grade students from the 27 state capitals in Brazil who were of ages 11-17 years or older. Variables analysed were dental pain within the last 6 months (yes/no) and the following sociodemographic factors: age, sex, race, type of school and maternal schooling (years of study: ≤8; 9-11; ≥12). The prevalence of dental pain in the 3 years was compared using the Rao-Scott test. Relative and absolute measures of socioeconomic (maternal education) inequalities in dental pain were applied using the slope index of inequality (SII) and the relative concentration index (RCI). Results: The prevalence of dental pain increased from 17.5% (95% CI = 16.9-18.2) in 2009 to 20.4% (95% CI = 19.7-21.1) in 2012, then to 21.8% (95% CI = 21.1-22.5) in 2015. All sociodemographic factors investigated were associated with dental pain in all survey years. There was an increasing proportion of the outcome in all categories of maternal education over the years studied. Absolute (SII) and relative (RCI) inequalities regarding of maternal education were found; these indicate higher levels of dental pain in the lower socioeconomic group in each study year. However, no significant changes in inequalities were found from 2009 to 2015. Conclusions: The prevalence of dental pain increased in the 2009-2012 and 2012-2015 periods, and social inequalities were found. Higher levels of dental pain persisted in the lower maternal education group. Inequalities remained stable over time. Broader actions to reduce the existing inequalities are needed and should be a priority for public policies.