| Bone defection as a difficult and indispensable problem has been researched by clinical surgeons for several centuries. Though autologus bones are seemed as the best choice, but large bone defection can not be repaired by autologus bone because of the scarce of resources. However, allogenic bones as biomaterials most similar to autologus bones have been applied widely in clinical medicine. They have three dimension pore cluster and better material and biology characteristics which result in stronger bone conduction and bone induction capability. But, since now, allogenic bones all derived from fresh human bones. As we know, fresh human bones resources are so little, coming from dead corpses and accidental trauma, that clinical application are restricted. It is also possible to carry bacteria to make transplantation become dangerous. How to resolve these problems? In this study, human bone tissues which have been fixed by fomalin for more than six months were used as raw materials to produce allogenic graft bones. Then physical and chemical properties, cellular toxicity and histocompatibility characteristics were studied to demonstrate the feasibility of application this kind of graft bones clinically.[Objectives]1. Obsolete bones which have been fixed in 10%formalin for more than six months were used to produce allogenic graft materials. Then residual formalin quantity was detected.2. From material and biology characteristics detection, the feasibility of clinically application of this kind of allogenic graft bones was obtained.-4-[Methods]1. Oxidation and enzyme digestion were used to obtain this kind of allogenic graft bone materials. And residual formalin quantity was detected by ways of water extraction.2. The properties of bone material were detected in the follow aspects: the aperture, the Ph values, the protein contents, the ratio of calcium to phosphorus, the fat contents and the varieties of Ph values.3. Half of Graft Bone Materials, which weight was 20g, were used to obtain the extracted solution. DMEM was employed as extracting medium. Rat L6 cells were cultured in the extracted solution. The biological properties, such as growth curve, proliferative ability and metabolism, were detected by inverted phase contrast microscope, MTT and flow cytometry. The other Bone Materials (l0g) were seeded by Rat L6 cells in vitro. Make use of inverted phase microscope and scanning electron microscope to observe cellular morphology.4. This kind of allogenic graft bone materials were implanted under the skin of mouse and into muscle. The hitocompatibility of this kind of graft bone materials was valuated through gross observation, local cellular immune response and HE staining. In the meantime, a segmental bone defect was created at two radiuses in each rabbit. This kind of graft bone materials were implanted into defects, the result of which was assessed by serial radiographic, biomechanical and histologic studies respectively.[Results]1. The residual formaldehyde of this kind of allogenic graft bone materials is below the standard level which is allowed. And in lots of aspects, such as appearance, color and luster, feature and so on, there are no significant different between this graft materials and the bone materials productions which have been used in clinical.2. This kind of graft materials was better than the bone material productions in the protein contents and fat contents. In the other aspects, they have no-5-significant different.3. L6 cells, which were cultured with the Bone Materials and extracted solution, grow well and proliferate rapidly. All properties indicated the Bone Materials have no significant influence for cells' proliferation, differentiation and cell cycle.4. After transplanting, we found the vital signs of animals were fine, and it had no effect on the behaviors and appetites of animals. In the testing of ectopia transplantation, the graft materials were also found to be able to conduct soft tissue to grow into them. And peripheral tissu...
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