Clinical manifestation and significance of dental fluorosis of children in endemic fluorosis areas and non-diseased areas

Objective To understand clinical manifestation, characteristic and difference of dental fluorosis of children in endemic fluorosis areas and non-diseased areas, and to provide index for diagnosing endemic fluorosis. Methods Twelve villages from mild to moderate and severe endemic fluorosis areas and 8 villages from non-diseased areas was sampled in stratified randomization and the dental fluorosis of children aging 8～12 years were examined with Dean's index in 4 063 individual. The fluoride levels in drinking water and urine of the children were determined with F-ion selective electrode method. Key subjects were followed up. Results Incidence of dental fluorosis was 55.7% in the diseased areas and 16.5% in the non-diseased areas with a significant difference(P0.005). Dental fluorosis of moderate and serious degree occurred only in higher level fluoride areas, while that of extremely light degree in the non-diseased areas. Conclusions Dental fluorosis is not only resulted from absorbing excessive fluorides, since dental fluorosis is also found in lower level fluorides areas. Moderate and serious degree dental fluorosis are the results of fluoride poisoning, and their manifestation are significant for clinical diagnosis of endemic fluorosis.