Epidemiologic study of children dental fluorosis in endemic fluorosis areas in Tianjin.

Objective To know the epidemiological characteristics of children dental fluorosis in endemic fluorosis areas in Tianjin. Methods Ten prevalent areas were selected and 55 villages were collected by cluster sampling in 2008. Such indicators of endemic fluorosis as the content of water fluoride in the investigated villages,the state of dental fluorosis among the children aged 8-12 years,the concentration of urine fluoride were investigated. Results The average rates of dental fluorosis were different among different areas(χ2=773.571,P=0.000) ,positively correlated with the content of water fluoride(r=0.924,P=0.000) . In serious prevalent areas,the average rates of dental fluorosis were different among age groups(χ2=16.351,P=0.003) . The geometric mean of urine fluoride was different among different areas(H=75.356,P=0.000) ,positively correlated with the content of water fluoride(r= 0.266,P =0.000) . In the same area,no significant difference was observed in the geometric mean of urine fluoride among age groups. Conclusion In Tianjin,endemic fluorosis is still very serious and the efficient control will be promoted.