Prevalence of dental fluorosis in regions supplied with non-fluoridated water in the brazilian territory: A systematic review and meta-analysis

Abstract

This systematic review and meta-analysis aimed to estimate and compare the prevalences of dental fluorosis in Brazilian cities supplied with non-fluoridated water and in locations that uses groundwater. In December of 2016, cross-sectional studies were searched in eight databases, including the “grey literature”. The prevalences were estimated through a mixed random effects model considering the locations as subgroups. The heterogeneity among the studies was assessed with I2 statistics and the Cochran’s Q test. A total of 1038 records were found, from which only 18 articles met the inclusion criteria and were subjected to analysis. The meta-analytic model estimated a prevalence of dental fluorosis of 8.92% (95% CI: 5.41% to 14.36%) in cities supplied with non-fluoridated water, and of 51.96% (95% CI: 31.03% to 72.22%) in cities supplied by artesian wells. The heterogeneity among the studies was high: I2 = 95% (p < 0.01) in the first subgroup of cities and I2 = 98% (p < 0.01) in the second subgroup. The prevalence was significantly higher (p < 0.001) in populations exposed to artesian well water, indicating that the presence of natural fluoride at high concentrations represents a risk factor for the occurrence of dental fluorosis.