Natural history and long-term impact of dental fluorosis: a prospective cohort study.

OBJECTIVE The study assessed longitudinal changes in the presentation of dental fluorosis and evaluated the impact of fluorosis on the perception of oral health among young adults. DESIGN AND SETTING Prospective follow-up study during 2011-12 of a population-based study in South Australia conducted between 2003 and 2004. PARTICIPANTS 8-13-year-old children initially examined in 2003 and 2004. MAIN OUTCOMES Dental fluorosis was assessed with the Thylstrup and Fejerskov (TF) Index. The impact on perceptions of oral health by the study participants and their parents was assessed with the Global Rating of Oral Health (GROH). Pairwise comparative analysis of the presentation of fluorosis was conducted at the individual and tooth levels. Multivariable models of changes in fluorosis were generated. An ordinal logistic regression model was used to evaluate the association between GROH with dental fluorosis, caries and other factors. RESULT A total of 314 participants completed the follow-up questionnaires and dental examination. Over 60% of teeth scored as TF 1 at baseline were scored as TF 0 at follow-up; 66% of teeth scored as TF 2 or 3 at baseline were scored as TF 0 or 1 at follow-up. In multivariable models, changes in fluorosis were not significantly associated with socio-economic factors or oral health behaviours, confirming that they were the result of a natural process. Perceptions of poor oral health were significantly associated with the number of untreated decayed tooth surfaces at follow-up, but not with fluorosis. CONCLUSION Very mild and mild dental fluorosis diminished with time. Dental fluorosis did not have a negative impact on perceptions of oral health.