Transformation of different calcium-phopshates after different implantation

The biocompatibility, biodegradation and in vivo transformation of four calcium phosphates (Ca-P) after implantation were investigated. The Ca-P materials (carbonatehydroxyapatite, CHA; F-substituted apatite, FI-IA; calcium-deficient apatite, AP; and magnesium-substituted tricalcium phosphate, beta -TCMP) were prepared and characterized using X-ray diffraction, FTIR and scanning electron microscopy (SEM). Dissolution properties were investigated ill acidic buffer (0.1 M KAc, pH 6, 37 degreesC). Sterilized materials were implanted in surgically created defects ill femoral diaphyses of rabbits for 30 days. Retrieved implants were examined histologically and by back-scattered SEM with energy dispersive system (EDAX).All materials showed biocompability and intimate interface with the hard tissues. FA showed the least, and CHA, the most extent of biodegradation. The Ca/P of the surfaces of implanted material were similar to that of bone apatite regardless of their original Ca/P. Conclusion: Ca-P materials differing in composition also differ in biodegradation. These materials partially transform to bone-apatite like regardless of their original composition.