“…The present study supports previous fi ndings that the prevalence of DDE is associated with the fl uoride concentration of the available drinking water, and that the occurrence of diffuse opacities can be a discriminating factor between the high-fl uoride and low-fl uoride groups [Suckling and Pearce, 1984;Cutress et al, 1985;Clarkson and O'Mullane, 1989;de Liefde and Herbison, 1989;Angelillo et al, 1990;Milsom and Mitropoulos ,1990;Nunn et al, 1993;Ekanayake and van der Hoek, 2003]. However, the mouth prevalence fi gures of 89.3% in 1983 ([F] 1.0 ppm), 48.5% in 1991 ([F] 0.7 ppm), and 32.4% in 2001 ([F] 0.5 ppm) for diffuse opacities in the current study ( table 1 ) are higher than that reported in other studies with similar concentrations of fl uoride in the public water [Cutress et al, 1985;de Liefde and Herbison, 1985;Angelillo et al, 1990;Milsom and Mitropoulos, 1990;Holt et al, 1994;Dini et al, 2000].…”