Reevaluation of Dental Fluorosis as Fluoride Biomarker

Objectives: In the WHO Technical Report Series 846, fluoride biomarkers were classified into three categories as contemporary markers(urine,plasma,saliva), recent markers(nail and hair) and historic markers(bone and teeth). The term, biomarker, is used widely in life sciences. However, fluoride biomarkers are still obscure in a practical meaning regarding appropriate use and overexposure of fluorides. The aim of this study is to ascertain the classification of dental fluorosis and enamel opacities in terms of biomarker concepts. Methods: the data were obtained from reports in retrospective epidemiological studies in fluoride and non-fluoride areas in Japan. These data were divided into dental fluorosis in fluoride areas, enamel opacities in non-fluoride areas and ambiguous enamel mottling in both areas. Results: Although several classifications of dental flurorosis and enamel opacities are still used in worldwide survey, we propose from the evaluation in this study that a trial classification of enamel mottling involves (1) dental fluorosis(DF), (2) idiopathic enamel mottling(IM), (3) white spots caused by demineralized enamel surfaces(WS), (4) injury spots caused by deciduous precessor during calcification of permanent teeth(IS) and (5) enamel hypoplasia(EH). Conclusions: In this classification, we were able to ascertain milder forms of DF as possible way of eliminating ambiguous enamel mottling resembling DF. The fluoride biomarkers in dental fluorosis should be evaluated with epidemiological and biological backgrounds and monitored using the time sequence analysis for non-fluoride enamel mottling without or less fluoride exposure.