Abstract
Normal hard tissues in human body include tooth enamel, dentin, cementum and skeletal bone. Tooth enamel, which is the only ectodermal derivative among them, contains about 96 wt% of inorganic component and at the highest of crystallinity. Tooth dentin has about 70 wt% of inorganic, and its calcification seems to be in close relationship to collagen. In this paper, problems of tooth enamel and dentin were shortly reviewed.
