[Dental fluorosis in children from Princesa Isabel, Paraiba].

Several communities in Paraíba have moderate or high levels of fluoride naturally present in the drinking water. A moderate prevalence of dental fluorosis (30-40%) has been observed in some areas where the levels of fluoride are regarded as "optimal" for the region (0.6 ppm). The aim of the present study was to determine the prevalence of dental fluorosis in Princesa Isabel, a city with "sub-optimal" fluoride levels (0.4 ppm). The sample comprised 142 schoolchildren (10- to 15-year-old subjects) randomly selected and examined by means of the TF (Thylstrup & Fejerskov) index. The clinical exams were carried out under indirect natural light by three calibrated examiners. Prior to the examination the teeth were cleaned and dried. Approximately 20% of the subjects examined presented with some degree of fluorosis. Seventy per cent were classified as TF 1 while 30% were classified as TF 2 to 5. The prevalence of fluorosis was higher in male subjects and in premolars. Although the observed prevalence of dental fluorosis was within the expected levels, other sources of systemic fluoride must be controlled. The observed prevalence of dental fluorosis is not a public health problem in this community.