Risk of enamel fluorosis in nonfluoridated and optimally fluoridated populations: considerations for the dental professional.

BACKGROUND: Few studies have evaluated the impact of specific fluoride sources on the prevalence of enamel fluorosis in the population. The author conducted research to determine attributable risk percent estimates for mild-to-moderate enamel fluorosis in two populations of middle-school-aged children.

METHODS: The author recruited two groups of children 10 to 14 years of age. One group of 429 had grown up in nonfluoridated communities; the other group of 234 had grown up in optimally fluoridated communities. Trained examiners measured enamel fluorosis using the Fluorosis Risk Index and measured early childhood fluoride exposure using a questionnaire completed by the parent. The author then calculated attributable risk percent estimates, or the proportion of cases of mild-to-moderate enamel fluorosis associated with exposure to specific early fluoride sources, based on logistic regression models.

RESULTS: In the nonfluoridated study sample, sixty-five percent of the enamel fluorosis cases were attributed to fluoride supplementation under the pre-1994 protocol. An additional 34 percent were explained by the children having brushed more than once per day during the first two years of life. In the optimally fluoridated study sample, 68 percent of the enamel fluorosis cases were explained by the children using more than a pea-sized amount of toothpaste during the first year of life, 13 percent by having been inappropriately given a fluoride supplement, and 9 percent by the use of infant formula in the form of a powdered concentrate.

CONCLUSIONS: Enamel fluorosis in the nonfluoridated study sample was attributed to fluoride supplementation under the pre-1994 protocol and early toothbrushing behaviors. Enamel fluorosis in the optimally fluoridated study sample was attributed to early toothbrushing behaviors, inappropriate fluoride supplementation and the use of infant formula in the form of a powdered concentrate.

CLINICAL IMPLICATIONS: By advising parents about the best early use of fluoride agents, health professionals play an important role in reducing the prevalence of clinically noticeable enamel fluorosis.