Fabrication And Biomedical Properties Of Porous Biphasic Calcium Phosphate Composite Ceramics

With the extraordinary development of science and technology in the 21^st century,biomedical materials have played an important role in the economic construction of society,especially in the research and clinical applications of biomedical science.Biological ceramic materials are gradually becoming one of the hottest points in the field of biological material because of their superior biocompatibility and bioactivity.As the most representative bioactive ceramic,hydroxyapatite?HA?and?-tricalcium phosphate??-TCP?,with their excellent biomedical properties,attract researchers'attention in the biomedical engineering field,especially in bone defect restoration and regeneration.To improve the problems including poor pore structure and slow degradation in commercially artificial bone prepared by HA and?-TCP microparticle powders,the porous BCP composite ceramics are fabricated by HA and?-TCP nanoparticle powders,the ceramic with controllable macro pore size distributions by adjusting the usage of the surfactant and controlling the program controlled high temperature calcination have lots of inter-connective structures which can promote the ingrowth of bone cells and the degradation of the materials.Therefore,this porous BCP composite ceramic can be further used as the biological ceramic materials for further clinical investigation and application in bone defect restoration and regenerationThis thesis synthesized HA and?-TCP nanoparticle powders as precursor materials by optimizing the experimental parameters,then prepared porous biphasic calcium phosphate?BCP?composite ceramics with controllable macro pore size distributions and investigated their biomedical properties.The main results obtained are as follows:?1?Optimized the experimental parameters of modified sol-gel method and chemical co-precipitation method.Synthesized and characterized HA and?-TCP nanoparticle powders with favorable thermostability by controlling Ca/P ratio,pH value,and washing solvent.?2?Prepared BCP composite ceramic green bodies with different pore size distributions by mechanical mixing method based on the obtained nanoparticle powders,using polymethyl methacrylate as organic micro pore-forming agent,using sodium dodecyl sulfate as surfactant to control the macro pore of porous BCP composite ceramics,and using ammonium bicarbonate to be the foaming agent.Fabricated porous BCP composite ceramics with controllable macro inter-connective pore size distributions after program controlled high temperature calcination.The macro pore size of BCP ceramics could be controlled among 100 to 600?m.?3?Investigated the biomedical properties of the porous BCP composite ceramics.The BCP ceramics were examed to have no cytotoxicity,satisfying cell adhesivity,well biodegradability and favorable biological activity by culturing with human dental pulp stem cells and soaking with simulated body fluid.