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Distribution of fluoride in clinically sound enamel surfaces of permanent upper incisors.

A more comprehensive examination of permanent human upper incisors supports previous conclusions that the pattern of development, the effects of abrasion, and the influence of dental plaque is largely responsible for the major changes in fluoride concentration which occur with age in sound enamel. It has become clear, however, that a much fuller history of individual teeth would be necessary for an unequivocal interpretation of such data.