Nano-hydroxyapatite effects on bone regeneration

Song Hua; Ren Xiang-qian; Wei Dong-xing

doi:10.3969/j.issn.2095-4344

Abstract：BACKGROUND:Hydroxyapatite materials have similar spatial structure and hardness to the natural bone matrix, but due to the imperfect early technology, there are some problems in the pore and degradation. OBJECTIVE:To compare the effects of nano-hydroxyapatite materials and hydroxyapatite materials in the repair of disconnected defects of the tibia in rats. METHODS:Thirty-six Sprague-Dawley rats were randomized into four groups, and a 5 mm disconnected defect model was established in the left tibia. Bone marrow mesenchymal stem cels/nano-hydroxyapatite complex was implanted into the experimental group, bone marrow mesenchymal stem cels/hydroxyapaptite complex into the control group, and bone marrow mesenchymal stem cels into the cel group. There was no treatment in the blank control group. At 2, 8, 12 weeks after implantation, X-ray measurement, hematoxylin-eosin staining, western blot assay were used for observation of bone repair, osteogenesis, and expression of type I colagen in the repair area. RESULTS AND CONCLUSION:After 12 weeks of implantation, in the experimental group, the newborn caluses covered the whole defect region and formed visible bridge connections, the scaffold was degraded mostly, a great amount of osteoid tissues were visible to form the bone trabecula with lamelar bone structure, and there were a lot of type I colagens; in the control group, the number of caluses in the defect area was increased, poor integration was found at the broken end, bone sclerosis developed, the scaffold was not completely degraded, bone trabecula <br> and lamelar bone formed, and a large amount of type I colagen was visible but lower than that in the experimental group; in the cel group and blank control group, no obvious bone regeneration was seen, and the expression of type I colagen was weak. These findings suggest that nano-hydroxyapatite is better than hydroxyapatite to promote bone regeneration.