Nano-hydroxyapatite has a high crystallinity after sintering and difficultly degrades in vivo. Due to the high degradation rate, nano-β-tricalcium phosphate is not conducive for the biological tissue to attach on the material in vivo, which is not conducive to osteogenic induction.OBJECTIVE:
To observe the bone formation and degradation performances of nano-hydroxyapatite/ nano-β-tricalcium phosphate biphasic ceramic artificial bone.METHODS:
Thirty-six Chinchilla rabbits were randomly divided into experimental group, control group and blank group, and the rabbits were used to establish the left radius bone defect model. The rabbits in the experimental group and the control group were implanted with nano-hydroxyapatite/nano-β-tricalcium phosphate biphasic ceramic artificial bone and nano-hydroxyapatite artificial bone respectively, and the blank group was not implanted with any materials. The bone formation and degradation performances were observed at 4, 8 and 12 weeks after implantation.RESULTS AND CONCLUSION:
X-ray film at 12 weeks after operation showed that the materials in the experimental group were basically degraded, the continuity callus grew through the bone defect site; the materials in the control group were not degraded obviously, and there was callus at the bone defect site; the bone defect in the blank group was not repaired. Histological observation at 12 weeks after operation showed that the material pores in the experimental group were filled with bone cells and osteoblasts, as well as a small amount of chondrocytes, the scattered cancellous bone appeared and the materials were completely degraded; the material pores in the control group were filled with bone cells, as well as a small amount of osteoblasts and chondrocytes, and the materials were not degraded completely; fibrous connective tissue and collagen fibers could be seen in the blank group. Scanning electron microscope observation at 12 weeks after operation showed that in the experimental group, the materials were degraded, and the bone defect sites were replaced with new bone cancellous bone; materials in the control group were not degraded, and most of the bone defect sites were replaced with new cancellous bone; no obvious bone reconstruction could be seen in the blank group. The results indicate that nano-hydroxyapatite/nano-β-tricalcium phosphate biphasic ceramic artificial bone has good degradation performances.RESULTS AND CONCLUSION:
Nie W, He W. Osteogenesis and degradation performances of nano biphasic ceramic artificial bone. Zhongguo Zuzhi Gongcheng Yanjiu. 2013;17(12): 2100-2107.