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Influence of low and high doses of fluoride on tooth germ development in rats.

The influence of fluoride on tooth germ development, especially mineralised tissue, is well documented in numerous dental publications, but there are few reports concerning the influence of fluoride on enamel organ and dental papilla cells. The aim of the study was to assess histologically the development of tooth germs of 20-day-old rat foetuses whose mothers drank water without fluoride or with low (10 mg) and high (110 mg) contents of natrium fluoride, starting from the 12th day of the pregnancy. The fluoride contained in drinking water in low as well as high concentration accelerated the development of enamel organ and dental papilla structures in rat foetuses. The acceleration was proportional to the content of fluoride in drinking water. No disturbances caused by high concentration of natrium fluoride were observed.