Fluoride Concentration in Human Fetal Enamel

Abstract

The fluoride distribution was determined along the developing human fetal enamel of 7 maxillary first incisors taken from fetuses aged 5–9 months. The fluoride concentration in the enamel from teeth of fetuses aged 5–8 months, which contained only forming enamel was higher in the youngest enamel near the cervical margin than in the earliest formed enamel at the incisal tip. In the developing enamel from the teeth of the 9-month-old fetuses, however, after the initial decrease in fluoride concentration from the cervical margin towards the border between the forming stage and the maturing stage, there was a rise in fluoride concentration as the forming enamel began to rapidly mineralize to become maturing enamel. This pattern seems analogous in the comparable stages of enamel development to that previously observed in developing enamel from teeth of experimental animals.

Fluoride concentrations of the surface enamel of children living in an optimally fluoridated community

“…When enamel begins to maturate, fluoride concentrates into the outer layers (20,21). The maturation continues posteruptively in the surface of recently erupted teeth, which, because of its permeability, is susceptible to exogeneous agents (22).…”

“…The fluoride concentradon of developing enamel has been shown to depend on the availablity of fluoride in the surrounding dssue fluid (19). When enamel begins to maturate, fluoride concentrates into the outer layers (20,21). The maturation continues posteruptively in the surface of recently erupted teeth, which, because of its permeability, is susceptible to exogeneous agents (22).…”

Possible Function of Matrix Proteins in Fluoride Incorporation into Enamel Mineral during Porcine Amelogenesis

“…One important conclusion in the literature (Hammarstrom, 1971;Speirs, 1975;Weatherell et al, 1975a;Ahlberg et al, 1975;Deutsch and Gedalia, 1982) is that the maximum fluoride content of the enamel tissue is attained in the early developmental stages, and that it decreases as the density of the tissue (or mineralization) increases. Several investigators (Weatherell et al, 1975b;Crenshaw et al, 1978;Crenshaw and Bawden, 1981) have suggested that there is an association between fluoride and matrix proteins, and that some of the fluoride, as part of the matrix, might be withdrawn from the tissue during mineralization.…”