[Formation of calcium phosphate crystals in pseudophysiological solution by SiC Whisker reinforced glass ceramics. Effect of Phosvitin on nucleation].

The effect of the phosphorylated protein, phosvitin, on the formation of the calcium phosphate crystal was examined in metastable calcium phosphate solution. Addition of glass ceramics caused consumption of hydrochloric acid, as a result of the dissolution of metal oxides. The activities of dissolution and nucleation were both high in the case of CPS-SiC. Phosvitin affected only the nucleation process, not the dissolution process. The decrease of phosvitin concentration after the addition of materials demonstrated adsorption of phosvitin by the material surface. The thermodynamic stability of solution after several days maintained equilibrium against tricalcium phosphate (TCP) and especially against octacalcium phosphate (OCP). From these results, it is concluded that glass ceramic implants have potential to stimulate hydroxyapatite formation, even in the presence of matrix substances.