A study is presented of human tooth enamel and its changes during heating. The measurements were done by methods of electron paramagnetic resonance, roentgen structural analysis and gaseous chromatography. A new effect has been found related to changes of enamel structure during heating. It was established that at T 170 degrees C there occurs reorientation of the crystallites of hydrohylapatite that form the structure of tooth enamel as well as changes of the properties of organic layers between these crystallites. Discussed are the general principles determining the structure and properties of minerals of biological origin. It is shown that the organic structure of the biomineral effects the properties of inorganic crystallites by means of the spatial geometric factor. This factor is finally related to the fact, that superficial energy of the crystallite contributes essentially in its general energy. The authors discuss the obtained results from the viewpoint of diagnosis and new treatment methods of diseases related to the biomineral of the human body.
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