Abstract
Apatite of biological hard tissues, especially, of enamel, dentin and bone was investigated by infrared spectroscopy, Laser-Raman spectroscopy, wide N. M. R. and X-raydiffraction.
1) At first, calcification of dentin was higher than that of enamel, but later that of enamel rapidly increased. Calcification of bone was higher than that of enamel and dentin at birth, but its progress was slow and it became lower than that of enamel and dentin, coming to maturity. Calcification of tooth substances progressed according to decrease of protein and CO32- was increased as maturing. Calcification of bone substances was not as clear as that of tooth substances. CO32- in enamel was substituted for OH- mainly, and PO43- partly. CO32- in dentin and bone was substituted for PO43 mainly.
2) Apatite of enamel contained bone water in its crystal, and apatite of dentin and bone had absorbed water around its crystal. A part of CO32- of enamel, dentin and bone was contained in the crystal lattice of apatite. CO32- of enamel was substituted for OH- mainly, CO32- of dentin was subsituted for PO43- more than for OH- and that of bone was for PO43- mainly. Its crystal of all enamel, dentin and bone had C-axis longer than A-axis. Inorganic particles of enamel were 700-300Å, and those of dentin and bone were 200-50Å.
3) F- in enamel was substituted for a part of OH-. When tooth substances were extracted for examination at a certain interval, the volume of F- apatite increased. When F- was spread on the surfaces of tooth substances, F- apatite was less than the former F-, and CaF was formed.
