Ash and fluoride contents of the different human foetal teeth from areas of low and high fluoride concentrations in the drinking water

Abstract

The fluoride and ash content of the different developing teeth were determined in 59, 8- and 9-month-old human foetuses derived from areas of low (about 0.1 p.p.m.) and high (0.5–1.0 p.p.m.) fluoride concentration in the drinking water. The uptake of fluoride in the developing foetal teeth from areas of elevated as compared with low fluoride concentration in the drinking water was significantly higher. Within the same area the percentage of the fluoride content of the 9-month-old foetal teeth appeared to be lower than that found in the analogous teeth of the 8-month-old foetuses. For the most part this was not statistically significant. Increased uptake of fluoride did not alter the ash content of the teeth. The sequence and rate of calcification in the different teeth in both areas appear to be steady from the initiation of mineralization until the eighth foetal month, and is in the order of first incisor, first molar, second incisor, canine, and second molar (A, D, B, C, E). In the 9-month-old foetuses the order changes to A, B, D, C, E reflecting the eruptive sequence.