[Infrared-spectroscopic studies of the carbonate apatite structure of dental hard tissues]

Samples of enamel, dentine and cementum were calcined at temperatures of 500 degrees C, 800 degrees C and 1000 degrees C. The infrared spectra recorded at these temperatures were evaluated quantitatively and qualitatively. With increasing temperature, the conversion of the primarily present carbonate apatite into hydroxyapatite increased. At 800 degrees C, a hydroxyapatite proportion of 83% was found. At that, the thermal treatment produced in the dentine an increase in the degree of crystallization from 62% to 100%.