Fluoride, dental fluorosis and tooth quality

Fluoride (F) has been a useful instrument in caries prevention. However, despite its wide use, there is a lack of information regarding the influence of long term F use on tooth quality.; The objectives of this study were: (a) to analyse the correlation between tooth F concentration ([F]) and dental fluorosis (DF) severity; and the correlation between tooth [F] and bone [F]; (b) to evaluate the influence of tooth [F] and DF severity in tooth quality (mechanical, material and structural properties); and (c) to create a continuous scale for DF severity.; For this study the following samples were analyzed: (1) 319 unerupted human third-molars from areas of sub-optimum and optimum F levels in the drinking water; (2) 111 erupted human teeth from two DF endemic areas; and (3) Bone and teeth from 70 mice exposed to a wide range F.; A weak correlation between tooth [F] and DF severity was seen in human teeth. In unerupted third-molars DF severity correlated (weakly) with dentin [F], but not with enamel [F]. In teeth from endemic areas of DF, DF severity did not correlate with tooth [F]. A good correlation between DF severity and tooth [F] was seen in mice. No correlation between bone and tooth [F] was seen in the human. In mice, tooth [F] correlated with bone [F].; In human teeth, dentin [F] correlated with structural, mechanical and material properties; enamel [F] correlated with mechanical and material properties; and DF severity correlated with mechanical properties.; In mice, tooth [F] correlated with tooth material and mechanical properties. DF severity correlated with mechanical property.; A continuous scale for dental fluorosis (VAS for DF) was created and validated.; In conclusion, the amount of F in tooth structure (enamel and dentin) is not a good biomarker for severity of dental fluorosis in humans. In humans ingesting optimum levels of F through their drinking water (0.7 to 1.0 ppm), tooth F concentration is not a good biomarker for total body F burden (bone [F]). Tooth properties (material, structural and mechanical), related to tooth quality, are influenced by tooth [F] and DF severity in human and mice.