[Different mechanisms of fluoride binding by bones and teeth]

Dental and skeletal hydroxyapatite have a high affinity to fluorine. For demonstration of possible difference in fluorine binding by teeth and bones fluorides were determined in teeth buds, milk teeth and femur of human fetuses. A relatively stable content of fluorides was demonstrated in teeth buds and in milk teeth of children In the fetal bone the level of fluoride was lowest, but according to literature data, it rises with age. The observed differences in fluoride levels may be due to different physicochemical properties of dental hydroxyapatite and bone hydroxyapatite, or to different regulation of fluoride binding.