| Large amounts of bone graft are frequently used to reconstruct the maxillofacial bone defects resulting from tumor resection, trauma, infection. Autograft and allograft bone are often used, but each has its limitations. To avoid the potential risk, artificial substitutes including bioceramics, polymers, alloys, and composite biomaterials have been studied. Among them calcium phosphate ceramics, e.g. hydroxyapatite(HA) and beta-tricalcium phosphate(P-TCP) have been extensively studied because their good biocompatible and osteoconductive properties. Sintered bovine bone, or true bone ceramic(TBC) is a porous biomaterial with a natural trabecular structure like that of cancellous bone and is composed of inorganic bone material. Because it is formed by sintering at a high temperature, TBC is not immunogenic, and no cytotoxicity is observed. Augmentation of the natural osteoconductivity of TBC with osteoinductive agents such as bone morphogenetic proteins (BMPs), bone marrow, and cultured osteoblasts has yielded promising osteogenic properties.Ostrich cancellous bone(OCB) is a kind of new xenogenic biomaterial which is rarely mentioned by other literatures. In our experiments, the OCBwas given a chemical management, then it was calcined to a high temperature and to be transformed to calcium phosphate ceramics(COB). Then the COB blocks were soaked in different concentration of sodium pyrophosphate (Na4P2O7-H2O, NP) solution and heated to 1100C to transform its constitution from HA into HA/p-TCP/NaCaP04 multiphasic calcium phosphate ceramics. In this study, we investigated the components, characterization, degradable ability, Biocompatibility of the multiphasic calcium phosphate ceramic and explored its application as the scaffold in bone tissue engineering.1. Compare of heterogenous ostrich and bovine cancellous bone: configuration, components and bending strengthObjective: To prepare the ostrich and bovine cancellous bone(OCB and BCB) and compare their configuration, components and bending strength . Methods: preparing the ostrich and bovine cancellous bone by chemical management. Then observing the surface configuration and analyzing the component proportion of water, organic and mineral material of the cancellous bone. Determining the bending strength of the material. Results: The OCB had different surface configuration and porosity structure with that of BCB. The pore size of OCB was even more uneven than that of BCB. The component proportion of water, organic and mineral material of the OCB and BCB was separately(6.85+0.10)%, (28.75+0.83)%. (64.40+0.78)% and(6.36+0.16) %, (29.79+0.28) %, (63.85+0.35) %. The average bending strength of OCB and BCB was separately ( 14.18+2.50) Mpa (22.93+3.93) Mpa. Conclusion: Both OCB and BCB had similar component proportion of water, organic , mineral material. The OCB material has different porosity characteristics compared with BCB and it might become another valuable heterogenous bone graft material.2. Preparation of ceramic-like ostrich cancellous bone scaffold andanalysis of its components and characterizationObjective: To prepare the COB scaffold and study its components and characterization. Methods. After the chemical management the OCB was heated to a high temperature and to be transformed to calcium phosphate ceramics. Then observing the surface configuration of the material by SEM and analyzing the following properties of the material: porosity, mineral composition, element ratio and bending strength. Results: The COB was a kind of porous calcium phosphate ceramic composed of hydroxyapatite(HA) and the Ca/P element ratio of COB was 1.613. the average porosity was (70.27+6.23 ) % and the pore size of most material was uneven. The average bending strength of COB was (1 92+0.63 ) MPa. Conclusion: The COB was a king of calcium phosphate ceramic with different porosity characteristics compared with other xenografts, for example, the bovine cancellous bone ceramic. The porosity characteristics of COB maybe make it more benefit to osteogenesis...
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