Abstract
This study examined the relationship between transient peak plasma fluoride levels (subcutaneous injections) as well as lower but relatively constant levels (subcutaneous constant infusion) and the occurrence of disturbances in the enamel mineralization of the rat incisor as determined microradiographically. The fluoride doses were administered for 1 week, and the animals were killed 2 weeks later. Once daily peak plasma fluoride levels of 10 µM were uniformly associated with disturbances in the mineralization of the enamel, but once daily peak levels of 5 µM were not. Neither were twice daily 5-µM peaks. Relatively constant plasma fluoride levels, which averaged 3.3 µM, were associated with an increased incidence of changes in enamel formation and levels of 4.7 µM consistently associated with disturbances in enamel mineralization. These findings suggest that (1) the rat is a better model for the study of human enamel fluorosis than previously believed, and (2) slightly elevated but relatively constant plasma fluoride levels are more likely to be associated with the occurrence of fluorotic disturbances in the mineralization of enamel than are the more rare high and transient peak levels.
*Abstract online at https://europepmc.org/article/MED/6956449
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Dental fluorosis: variability among different inbred mouse strains.
Concurrent with the decline in dental caries has been an increase in the prevalence of dental fluorosis, a side-effect of exposure to greater than optimal levels of fluoride during amelogenesis. The mechanisms that underlie the pathogenesis of dental fluorosis are not known. We hypothesize that genetic determinants influence an individual's
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Effects of fluoride on the expression of beclin1 and mTOR in ameloblasts
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Enamel fluorosis related to plasma F levels in the rat.
The purpose of this long-term study was to investigate disturbances in enamel mineralization associated with low, but relatively constant, plasma fluoride levels produced by constant infusion or with fluctuating plasma fluoride levels caused by drinking fluoridated water. Weanling rats were raised for 8 weeks on low-fluoride food and water containing
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Uncoupling protein-2 is an antioxidant that is up-regulated in the enamel organ of fluoride-treated rats
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Fluoride affects enamel protein content via TGF-B1-mediated KLK4 inhibition
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