Dental fluorosis occurs during tooth development especially between the ages of 6 months to 5 years, from the overexposure to fluoride. Teeth are generally composed of hydroxyapatite and carbonated hydroxyapatite; when fluoride is present, fluorapatite is created. In high concentrations fluoride can cause yellowing of teeth, white spot, and pitting or mottled of enamel. Consequently, the teeth look unsightly. Fluorosis can not occur once the tooth has erupted into the oral cavity. At this point, fluorapatite is beneficial because it is more resistant to dissolution by acids (demineralization). The incidence of dental decay in those teeth is very small. more...
Although permanent teeth are affected, occasionally the primary teeth may be involved. The symptoms are easy to recognize. Initially, there may be a few white flecks or small pits on the enamel of the teeth. Later, there may be brown stains. Dental fluorosis and dental caries seem to go hand in hand.
The disease is more prevalent in rural areas where drinking water is derived from shallow wells or hand pumps. The disease is more likely to occur in areas where the drinking water has a fluoride content of more than 1ppm (part per million), and in children who have a poor intake of calcium.
The only effective public health measure to prevent dental fluorosis is to limit the fluoride content of drinking water to 1 ppm or lower by using deep bore drinking water supplies. An adequate daily intake of calcium is also protective . Dental fluorosis can be cosmetically treated by a dentist, thereby removing some of the yellowing and spotting of the teeth. Since the staining is intrinsic to the teeth and not superficial, the success of such treatment is limited.
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