Tooth loss over 13 years of follow-up: Can regular dental visits reduce racial and socioeconomic inequalities?

OBJECTIVES: To assess if regular dental visits modify the effects of social and racial indicators on the incidence of tooth loss. METHODS: This is a longitudinal analysis using data from the Pro-Saude Study. In 1999-2001, 3253 civil servants responded to self-administered questionnaires, and then in 2012-2013, with 19% attrition. The outcome was any increase in self-reported tooth loss, measured in four ordered categories (none, one or few, many, all or almost all). Main variables included income, education, race/ethnicity and an adapted version of Everyday Discrimination Scale. The dental visit was dichotomized into regular and problem-oriented attenders. Potentially confounding factors were age and sex; effect modification was estimated using the relative excess of risk due to interaction (RERI). RESULTS: An increase in the tooth loss category was reported by 23.1% of the individuals over 13 years of follow-up. Among problem-oriented attenders, 27.3% reported an increase against 20.4% in regular users (p<0.01). Interaction results are inconclusive. Even though not significant, either antagonism or synergism were observed: between lower income and problem-oriented (RERI = -0.22; 95%CI: -0.75: 0.31), being Black+Brown and problem-oriented (RERI = -0.25; 95%CI: -0.64: 0.14), discrimination and problem-oriented (RERI = -0.15; 95%CI: -0.55: 0.25), and between having less than university degree and being problem-oriented (RERI = 0.21; 95%CI: -0.19: 0.62). CONCLUSIONS: Regular attenders from advantaged groups seem to benefit more from dental care than disadvantaged groups, increasing unfair inequalities. Inconsistencies in current findings warrant further investigations. CLINICAL SIGNIFICANCE: Regular attenders from advantaged groups seem to benefit more from dental care than disadvantaged groups, increasing inequities, but the effect size of the Relative Excess of Risk due to Interaction was not large and was inconclusive.