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Objective: large mandibular defect repair is still not well resolved. The existing variety of methods, such as autogenous bone graft, allograft implantation of metallic materials, implantation of artificial organic polymer materials, and so have some limitations. The purpose of this study is based on the principle of bionics design and development of nano-ceramic artificial materials with a high degree of biocompatibility and bioactivity in vitro and in vivo detection. Methods: acid-soluble law from bovine tendon the crude collagen type I, by salting out, dialysis, lyophilization purification refined type I collagen block. By UV spectrophotometry, amino acid analysis, conventional tissue sections, scanning electron microscopy to detect type I collagen refined. Two nano-ceramic (nano-hydroxyapatite and nano-calcium phosphate) and refined purification of type I collagen composite in accordance with the bionic method and self-loading technology, nano-ceramic artificial bone scaffold. Using the general observation, scanning electron microscopy, X-ray diffraction analysis, porosimetry method for analysis of the two scaffold. Cultured rabbit bone marrow stromal cells isolated from rabbit bone marrow. The amplification induced differentiation rabbit osteoblasts, cell morphology, determination of alkaline phosphatase activity, the calcified nodule detection (Von Kossa staining) and flow cytometry cell cycle and DNA analysis of the induced in rabbit Bone cells were identified. After the identification of rabbit osteoblasts were seeded in culture, two nano-ceramic artificial bracket particles of hydroxyapatite / type I collagen composite artificial bone scaffold and type I collagen scaffold as a control, using an inverted microscope and scanning electron microscopy osteogenic The growth of the cells the four scaffold around and surface to evaluate the biocompatibility of the scaffold and cell activity. Production of rabbit skull defect model (of 5 Pass skull defect), Zhejiang University, a master's degree thesis implanted the four scaffold and a blank, a total of eight, four simple implant scaffolds, four implanted autologous into The bone cells composite materials training block. Rabbits were sacrificed at 2, 4, 8 and 12 weeks, respectively, digital X-ray, conventional histological observation scaffolds the histocompatibility, biological activity in the body. Results: The purified collagen I absorbance at 225nm or so, 24.85% glycine, tryptophan-free, lyophilized type I collagen scaffold was loose, spongy, having a pore size of 100 30Oum and porosity of more than 90%. The two nano ceramic artificial scaffolds Movement loose sponge-like, having a 100-300um pore size and porosity of more than 90%, the X-ray diffraction analysis of the internal nano-ceramic nano-scale, Crystal imperfect development, having a structure similar to natural bone, Scanning Electron Microscopy two nano-phosphate are deposited on the surface of the collagen scaffold, similar to natural bone phosphate arranged in the surface of the collagen structure. Rabbit stromal cells cultured in vitro amplification, after induction with the typical morphological characteristics of osteoblasts, alkaline phosphatase staining positive, calcified nodules von one Kossa staining positive cell cycle and DNA analysis: GO GI proportion was 89.3 % GZ S ratio as 10.7%, and gz / GI DNA content ratio of 1.956. Rabbit osteoblasts cells grow well around the scaffold surface, having the typical morphology of osteoblasts. The four scaffolds implanted rabbit skull defect model comparative study, does not appear acute or chronic immune rejection, the two nano ceramic artificial inherent about four weeks, a large number of new capillaries, the 12 Zhou Xinsheng bone completely repair of bone defects and the formation of mature trabecular bone structure. Control bracket can not be fully restored skull defects, nano-ceramic artificial bone for about 3 months or so completely degraded. Osteoblast scaffold materials in culture composed of bone faster than the corresponding pure material implanted group. Conclusion: The purified collagen correspond to the characteristics of type I collagen, the lyophilized collagen I block having the spatial structure of the bone scaffold material suitable as. Rabbit stromal cells cultured in vitro amplification, can be induced to differentiate into bone cells, and with high proliferative capacity, suitable as seed cells for bone tissue engineering. Two nano-ceramic artificial bone scaffold similar to natural bone microstructure and suitable as three-dimensional structure of the artificial bone scaffold seeded in four scaffold composite culture found no material cytotoxicity, in vivo experiments have good osteogenic effects and suitable for the in vivo degradation rate, and has excellent biological activity, with bone conduction and bone guided osteogenic effect is good, better than particulate light-yl apatite / I type collagen composite bone scaffold, and collagen type I scaffolds. Scaffold composite culture of osteoblasts to form bone better than the corresponding pure material implanted group.
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