| It has been verified by the home and abroad research that porous degradable tricalcium phosphate ceramic (P-TCP) took on a perfect physic-chemistry performance . It had excellent biocompatibility and biodegradable capability. This material could induce the production of new bone and played the role of osteophony to repair bone defects,hence it was an ideal bone transplanting materials. But until now there isn't an ideal preparation method of p-TCP bioceramics. In this paper the salt-melted preparation technology was discussed. By force of testing the performance of prepared tricalcium phosphate ceramic,this paper briefly analysis the effect of the proportion and granule degree relation match of the aggregate and the pore-making agent on the performance of P-TCP bioceramics in the preparation of raw materials. At the same time this paper discussed the influence of different sinter technologies and different technique parameter in on the performance of P-TCP bioceramics.In order to find out the mechanism of bone growth and biodegradation of this kind materials animal experiment was adopted in this paper,by use of SEM,EPMA and polarizing microscope it discussed the transformation of porous bioceramic after implanted in rabbit's femur.In this experiment we got some important findingsFirstly,after implanted the material began to degrade indeed. Along with the swarming of the body fluid,massive macrophagocytes and osteoclasts launch into the pores of material. There are two kinds of processes in degradation. One was the dissolution effect of body fluid. By force of the experiment of the material's dissolving in simulate body fluid we find this kind of effect is very limited. The other was the degradation process induced by cells. Macrophages or osteoclasts can heighten the consistence of hydrogen ions in part circumstance contacted with material or interior cells by chemical reaction,which can accelerate the degradation of the material. Secondly,calcium ion and hydrogen ion were the prerequisite raw material of bone formation. And bounds of calcium ions and hydrogen ions produced by the degradation of material provide the activity of osteoblastics affluent material basis,which accelerated the formation of new bone. At the same time because of the insolubility of calcium phosphate,topical extortionate concentration of calcium ions and phosphate ions,the vary of PH value and the effect of osteoblasts and proteins in oregano-bone matrix,the calcium ions and phosphate ions gave birth to crystal nucleus and came into being osteo-salt deposition,furthermore to form mineralized bone. Finally,at the host osseous lamella far away the implanting area we found some material granules. In our opinion this phenomenon was realized bythe cells' effect of swallowing and transport. The formation of new bone was not merely achieved by the process of degradation and recrystallization. Because of the conformity of material and bone in component,by virtue of the energy offered by organized eozymes inside cells,with the help of protein the life element such as C,N,and O entered the material and achieved the information of new bone by rebuilding the structure of inorganic material. Whereas because we hadn't well-established evidence to prove it this was merely our presumption. We hope in the future using X-ray and TEM can help us make clear the transformation process of the inorganic material after implantation in detail.After implanted in host bone,bioceramics not only can play the role of bracket for bone growing but also can degrade and afford osteoblasts enough calcium and phosphate ions. So it will induce the new bone growing,participate in the vital process of host bone,and finally integrated with the host bone and become a portion of the organic new bone. Many live cells such as make important contribution to the transformation. They accelerate the biodegradation and absorption of implanted material,facilitate the generation and development of new bone. Meanwhile they make dynamic balance between bone growing and bon...
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