Comparative Examination of Natural Apatite Crystal and Biological Apatite Crystal

Abstract

Apatite crystals include both natural apatite crystals and biological apatite crystals. We analyzed the difference between natural apatite crystals and biological apatite crystals to investigate the possibility of using natural apatite crystals as a standard sample of quality of biological hard tissues. By EPMA analysis and the X-ray diffraction method, natural apatite crystal samples were shown to be fluorapatite. On the microscopic by Raman spectroscopic analysis method, the four Raman bands of the phosphate were also confirmed in the natural apatite crystals, the enamel apatite crystals, and the mandible apatite crystals. In natural apatite crystals, the Raman band of 964 - 965 cm^-1 shifted to the higher wavelength side compared to the biological apatite crystal. In the mandible, the difference of apatite crystal orientation was observed due to the site of cortical plate and trabecular bone.