Dentin in severe fluorosis: a quantitative histochemical study.

Dentin responds to different alterations in the enamel with hypermineralization, and is a biomarker of fluoride exposure. We hypothesized that severe fluorosis would lead to hypermineralization of the dentin when the enamel was severely affected. We used scanning electron microscopy and quantitative electron-probe microanalysis to compare dentin and enamel from healthy and fluorotic teeth. The dentin in fluorotic teeth was characterized by a highly mineralized sclerotic pattern, in comparison with control teeth (p < 0.001) and fluorotic enamel lesions (p < 0.001). Enamel near the lesions showed hypercalcification in comparison with dentin (p < 0.001). In response to the effects of severe fluorosis in the enamel, the dentin showed hypermineralization, as found in other enamel disorders. The hypermineralization response of the dentin in our samples suggests that the mechanism of the response should be taken into account in dental caries and other dental disorders associated with severe fluorosis.