Fluoride and Calcium Content of Enamel Organ, Muscle, Liver and Plasma in Rats

Abstract

Nine-day-old rats were given oral fluoride doses (0.5 μg F/g body weight). Plasma, enamel organ, muscle and liver samples were collected from nondosed pups (baseline) and 15,30,60 and 120 min after the dose. Samples were assayed for fluoride and calcium concentrations. Adult rats were given 20 ppm F water for 6 weeks, and the same tissues were sampled and assayed for fluoride concentrations only. In the first phase of the study, enamel organ had significantly higher fluoride and calcium content than liver and muscle. In adult rats the fluoride content of enamel organ was again significantly higher than for liver and muscle.

The Impact of Fluoride on Ameloblasts and the Mechanisms of Enamel Fluorosis

“…When plasma fluoride levels associated with enamel fluorosis in different species are compared, the values appear in the same range in rodents, humans, sheep, and pigs (Angmar-Månsson et al, 1976;Fejerskov et al, 1979;Angmar-Månsson and Whitford, 1982Andersen et al, 1986;Bawden et al, 1992;Milhaud et al, 1992). Hence, plasma fluoride values are currently the best way to compare effects of fluoride in relation to the development of enamel fluorosis between and among different species.…”

“…There is no evidence that exposure of developing teeth to physiological levels of fluoride, in vivo (Smith et al, 1993) and in organ culture (Kerley and Kollar, 1977;Levenson, 1980;Bronckers et al, 1984a;Bawden et al, 1992), affects tooth morphogenesis, cell proliferation, or differentiation of ameloblasts. Even in highly fluorotic teeth, the size and form of the teeth are not changed (e.g., Kierdorf and Kierdorf, 1997).…”

CRAC channels in dental enamel cells

“…Enamel contains the highest Ca 2+ content of all bioapatites. Compared to other tissues, enamel contains more than 9 times the Ca 2+ content of muscle or liver [31]. Most of the Ca 2+ (~90%) found in enamel is incorporated during maturation [19].…”

Recent observations on enamel crystal formation during mammalian amelogenesis

“…With respect to the fluoride content in forming enamel, it was well documented that the maximum fluoride content of the enamel tissue is attained in the early developmental stages , but there is uncertainty as to whether part of the fluoride incorporated in forming enamel tissue might be lost during the subsequent developmental stages (Bawden et al, 1992). In this regard, we found that some of the fluoride in forming (pig and rat) enamel was removed with the extraction of organic matter, mostly amelogenins in aggregated forms (Aoba et al, 1989a).…”