Dental fluorosis and nutritional status of 6- to 11-year-old children living in rural areas of Paraíba, Brazil.

The aim of this study was to investigate the relationship between nutritional status and dental fluorosis in areas with fluoride in the drinking water in Paraíba, Brazil. Rural villages of comparable low socio-economic status and stable water fluoride levels were selected. Lifelong residents (6-11 years old, n = 650) were examined for nutritional status (height-for-age index; WHO methods) and dental fluorosis of central incisors and first molars (TF index). The sample was divided into three groups according to fluoride levels in the drinking water: low (below 0.7 ppm F, n = 164), medium (between 0.7 and 1.0 ppm F, n = 360) and high (above 1.0 ppm F, n = 126). Dental fluorosis was observed in 30.5, 61.1 and 71.4% of the children in these F groups, respectively. The prevalence was significantly related to the water F concentrations (chi2 = 59.93, d. f. = 2, p<0.001). The severity of dental fluorosis ranged from TF 1 to 3 in the low F group and up to 7 in the others. Malnutrition prevalence was approximately 20% in all F groups, but was unrelated to dental fluorosis. The fairly high prevalence of dental fluorosis observed suggests that other factors may be operating.