| Once stepping into the modern society with ever-developing science and technology, whatever peace time or war time, human beings are challenged by the increasing morbidity rate of musculoskeletal trauma., which mainly presented with the form of long segmental comminuted fractures. In peaceful period or war time, natural disaster, the increasing traffic accidents, or high-energy weaponry, all contribute to the complexity of the pictures of wounds and trauma, which usually give rise to the severe tissue defects, especially the long segmental bone defects. Thus the treatment and salvage of involved wounded limbs become more difficult, in the long run, the increasing disability and impossible rehabilitation looms.In treating bone defects, up to now, the most efficient and classical method lies in the adoption of autografts, whose operation and principle has set a "gold standard" for the ensuing treating regime in the orthopedic field. But the traditional treatment by way of bone autografts is restricted by the resources of bone. On the other hand. the bone allografts and bone xenografts are perplexed by the immunogenicity and the possibilities of crossinfections and bacteriaviral transmission through bone grafting materials. All the abovementioned shortcomings limits the utilities of bone grafts. So researchers turn their focuses to the artificial bone implant substitutes. On this basis, some artificial implant materials, such as modified natural biomaterials, bioceramics, and high-molecular polymer, are developed; however, there still exist some deficiency on their biocompatibility, mechanical behaviors and degradation rates, that is the reason why these materials could not be widely used in treating bone defects in the orthopedical practice.The researches on the fabrication and manufacturing ofbBiomimetic compound materials have ever been the key field of bone tissue engineering. The new trend of manufacturing engineered bone materials is combining two or more biodegradable constituents together in an integrity, which hold the characters of complementing each other, in a certain method and proportion, in an attempt to construct the scaffolds satisfying the needs of bone tissue engineering. The compound scaffold materials should have a good balance between degradation rate and natural osteogenesis after implanted in defect sites, except for good biocompatibility and some extent of mechanical intensity. In the orthopedic practice and clinical researches, the current defect-repairing compound biomimetic implants are hard to overcome the deficiency of mismatch between degradation rate and natural osteogenesis Therefore, the selection of constituents and its mixture proportion of compound scaffolds in fabricating bone engineered-oriented scaffolds has become an unavoidable road to achieve the goal.To some degree, This study aiming at solving above problems andscreening out the optimal formula ratio of components in the biomimetic scaffold implants. By using the techniques of Rapid Prototyping Manufacturing (RPM) combined with Thermally Induced Phase Seperation, we fabricate a bioactive biomimetic bone, on which foundation, material biocompatibility, in vitro degradeability and mechanical intensity are undergone testing, also an in vivo bone-repairing processs are observed by implanting this biomimetic bone in the rabbits radii defect sites.This study can be subdivided into the following parts:1. A prospective study of in vitro degradation of different component ratio polymer/TCP compound materials prefabricated by modified TIPS(Thermally induced phase seperation method collocated with solvent-casting paniculate -leaching method).2. Mimic the in vivo fluid environment and have the biomimetic bone immersed in it to undergo the process of degradation, aiming at offer reference data for further in vivo implanting research.3. Manufacture the biomimetic bone by using Rapid Prototyping Manufacturing (RPM).4. Biological evaluation of polymer/TCP comp...
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