Esthetically objectionable fluorosis attributable to water fluoridation.

OBJECTIVE: We compared estimates of fluorosis prevalence and risk attributable to fluoridation using an index applied to the entire dentition and to the maxillary anterior teeth. We also estimated the prevalence of perceived esthetic problems attributable to current fluoridation policy (Attributable Burden).
METHODS: Fluorosis prevalence estimates were obtained from the National Survey of Oral Health in US School Children (1986-87) for the 1839 survey children aged 12 -14 years who were scored for fluorosis, had never received fluoride drops or tablets, and had lived in only one home. For each child we calculated Dean's fluorosis index, and an anterior fluorosis index (value of the highest scored maxillary anterior tooth). We used each index to calculate risk of fluorosis attributable to fluoridation by subtracting at each level of severity the prevalence of fluorosis among those living in low fluoride areas (F <or= 0.3 ppm) from the prevalence among those living in optimally fluoridated areas (0.7 ppm F <or=1.2 ppm). Findings from five published studies were used to calculate risk of perceived esthetic problem attributable to fluorosis, by severity, i.e. the difference in the mean percentage of respondents who were satisfied with the appearance of their teeth with and without fluorosis. Finally, Attributable Burden was estimated by summing the products of risk of perceived esthetic problems attributable to fluorosis and risk of fluorosis attributable to fluoridation for each level of fluorosis severity.
RESULTS: Prevalence of fluorosis, very mild or greater, was 26% with Dean's Index, which was significantly higher than the 18% figure calculated with the anterior index. Using the anterior index, fluoridation was a risk factor for very mild (attributable risk = 15%) and mild fluorosis (attributable risk = 3%). Risk of fluorosis (very mild or greater) attributable to fluoridation was significantly higher when calculated from prevalence estimates using Dean's Index than estimates calculated with the anterior index (24% versus 18%). The mean values of risk of perceived esthetic problems attributable to very mild and mild fluorosis were 9% and 33%, respectively.
CONCLUSION: We found that approximately 2% of US schoolchildren may experience perceived esthetic problems which could be attributed to the currently recommended levels of fluoride in drinking water. The findings further suggest that both estimates of fluorosis prevalence and risk of fluorosis attributable to fluoridation will be higher when calculated with an index applied to the entire dentition. Data were unavailable for fluoridated toothpaste and diluted formula consumption, thus the risk of fluorosis attributable to fluoridation may be overestimated if consumption was higher in fluoridated areas. The risk of perceived esthetic problems attributable to fluoridation must be weighed against its lifetime benefits and the associated costs of alternative solutions such as educating parents about appropriate toothpaste use and lowering the fluoride content of children's toothpaste.