Increase in dental caries and change in the socioeconomic profile of families in a child cohort of the primary health care in Northeast Brazil

Factors associated with increases in dental caries and changes in the family socioeconomic profile were investigated in a paediatric primary health care (PHC) cohort in Northeast Brazil during the implementation of social and income transfer programmes. A prospective analytical study compared data from two surveys on caries in primary dentition conducted in 2006 (age: 18-36 months, n = 1045) and 2010 (age: 5-7 years). Data from the sample recruited and re-examined in 2010 (n = 469) were analysed. Prevalences (P) and the mean primary decayed, missing and filled teeth (dmft) index, cumulative incidence and mean increase were calculated. Differences (p ≤ 0.05 and 95% CI) in dmft ≥1 were identified via McNemar's test. Differences in the mean dmft were evaluated according to socioeconomic variables (Kruskal-Wallis test and p ≤ 0.05). Multivariate analysis with a negative binomial model was used for the risk factors associated with increasing dmft. In the univariate analyses, nonparametric methods (Kruskal-Wallis test) were used to compare subsamples. Variables with p ≤ 0.20 were included in the multivariate model and retained when p ≤ 0.05. The prevalence and mean dmft (18-36 months and 5-7 years: p = 28.6 and 68.9%, mean = 1.01 and 3.46, respectively) and variation in mean dmft changed significantly (p