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Hydroxyapatite and the inorganic component of the human bone tissue have the same chemical structure, as bone repair materials, their biocompatible, osteoconductive, osteoinductive superb, and thus hydroxyapatite as a bone repair material Clinical Application frequently reported, but poor mechanical properties of hydroxyapatite, difficult to shape, largely limits its application. Hydroxyapatite combined with other materials to avoid weaknesses is a hot topic of research in this field, and has made some progress, but so far there is no ideal can be used in clinical bone repair material come out. In numerous studies, bone repair materials into injectable composite with of nanoscale hydroxyapatite and calcium sulfate for medical-reported, and animal studies of this material has not been publicly reported, which is the entry point of this topic . Explore first prepared by the reaction conditions close to the human body hydroxyapatite size hydroxyapatite, injectable nano artificial medical calcium sulfate hemihydrate composite, adjusting the ratio of ingredients. Then through composite clotting time, compressive strength tests to study the structure and properties of the investigated degradation of the composite material in simulated body fluids (SBF), and preliminary study of the degradation mechanism. In the cytotoxicity experiments visits composite bone repair material security, for animal experiments, repair rabbit femoral defect by 2, 4, 6, 8, 10, 12 weeks after X ray, histological and electron microscopy observe, evaluate its role in the repair of bone defects. The experimental findings: (1) Synthesis of nano-hydroxyapatite crystal rod-shaped, about 65nm in length, width ranging from 10 to 20 nm, and hydroxyapatite in human bone tissue close. (2) The compressive strength of the composites ranged between human cancellous bone and cortical bone strength. (3) The composite degradation in vitro simulated body fluid (SBF) absorption experiment, constantly releasing calcium and phosphorus elements can give bone growth, compared to the pure the CSH material or pure hydroxyl apatite material release speed, provide a lot of The source of calcium and phosphorus sources. (4) composite cytotoxicity grade of 0 or 1, and the animals implanted muscle tissue degradation experiments no edema, no purulent discharge, no muscle Ban marks, fibrosis and necrosis, suggesting that its biological phase The capacitive good. (5) composite material is injected into the rabbit femur bone hole defect, six weeks after bone hole has completely healed, and the blank control group has just begun to have significant healing phenomenon, indicating that the material has good bone repair.
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