Natual Fluoride and Fluorosis in 14-year-old Yemeni Adolescents

Fluoride in water has been established to be caries preventing in small doses of up to 1 ppm F. Above 2 ppm F fluorosis can develop. In a recent visit to Yemen, fluorosis was observed to be rampant among the 14 year-old subjects examined for malocclusion. An exploratory study was carried out to assess the extent of the problem. Objectives: To determine the prevalence of fluorosis observed in a representative sample of 14-year-old adolescents of Yemen. Methods: A random sample of 2,400 14-year-old Yemeni adolescents, equally distributed by gender, zone and locations participated in the study. Fluorosis was identified using photographs for Dean's Fluorosis Index downloaded at the World Health Organization website. No attempt was made to determine degree of severity of fluorosis. Photographs of identified cases were randomly taken for record purposes.Fluoride concentration from water samples at study locations were analysed.Results: Fluorosis was found in 30.8% of all subjects examined. Slightly more males(32.3%) than females (29.3%) were observed to have varying degrees of fluorosis. Fluorosis was also observed more among children living in rural areas(31.9%)than urban children(29.7%. None of the differences however were significant. When compared by zones, adolescents living in the south(46.9%) or east(49%) of Yemen were found to have almost two times or more with fluorosis than all other zones (North=15.2%, Central=20%, West=22.9%). The differences were found to be significant at p=0.0001. Fluoride concentration in natural drinking water taken from study locations was found to be between 0.2 – 3.8 ppmF. Conclusions: Findings from this study found fluorosis to be significant among Yemeni adolescents. A more refined and detailed national study is recommended, findings of which will be useful in the future planning to control the extent of fluorosis in Yemen.