Dental fluorosis in primary dentition in an endemic hydrofluorosis area.

Objective. The aim of the present study was to estimate the prevalence of d ental fluorosis in primary dentition of a San Luis Potosi children populati on, and its association to fluoride concentration in drinking water and uri ne. An additional objective was, to develop, validate, and test a specific index for dental fluorosis in primary dentition. Material and methods. From May 1997, to January 1999, we conducted a cross-sectional study to assess the prevalence of dental fluorosis in primary dentition. Study subjects wer e 100 children aged 3-6 years, selected at random from three kindergartens in three risk areas of San Luis Potosi. The specific index of dental fluoro sis for primary dentition (Dental Fluorosis for Primary Dentition Index-DFP DI) was validated by estimating fluoride concentrations in enamel of teeth with and without dental fluorosis. The Kruskal-Wallis test was used to asse ss the association between fluoride concentrations in drinking water and ur ine,with dental fluorosis; the association between risk area and dental flu orosis was assessed with the Mantel-Haenszel chi(2) test. Results. The prev alence of dental fluorosis in primary dentition was 78%; primary molars wer e most affected in both maxillae and the predominant color was a non-glossy white appearance. We found a strong direct correlation (r=0.93) between fl uoride concentrations in primary teeth and the DFPDI. Associations were fou nd between fluoride concentrations of drinking water and urine, with dental fluorosis (Kruskal-Wallis p=0.00001), and between risk area and dental flu orosis (Mantel-Haenszel chi(2)p=0.00001). Conclusions. DFPDI allowed adequa te identification and grading of dental fluorosis in primary dentition. It is important to detect the initial toxic effects of fluoride exposure to pr edict dental fluorosis in permanent dentition and skeletal fluorosis.