Prevalence and severity of fluorosis in the primary and permanent dentition using the TSIF

This paper reports on the prevalence and severity of dental fluorosis in the primary and permanent teeth and the tooth surfaces of 262 school children aged 6-18 years from two communities in KwaNdebele (South Africa), the first with 8-9 ppm F-, and the second with 0.6-1.6 ppm F- in the drinking water. The Tooth Surface Index of Fluorosis (TSIF) was used to measure the degree of fluorosis. In both areas, the population prevalence, for primary and permanent teeth was more than 90 per cent. For the lower F- area, 40 per cent of tooth surfaces were free of fluorosis compared with only 22 per cent in the high F- area. Of the surfaces affected by fluorosis in the high F- area, 37 per cent scored in the categories 4-7, compared with 6 per cent in the lower F- area. This difference in severity was found to be statistically significant (P<0.001). This study has shown that, in two areas with significantly different levels of fluoride in the water supply, the population prevalences of fluorosis were similar, but significant differences existed in severity. The World Health Organization 1984 guidelines for Drinking-water Quality recommend that 1.5 ppm F- is the maximum acceptable concentration in drinking water but this may not be appropriate for South Africa.