| Bone defect is the most frequently encountered war injury cases under modern war situation. With respect to the special features of war injury, it's necessary to select the bone graft materials with care to satisfy its need. When meeting this goal, we should take into consideration of a few aspects pertinent to the graft materials, which include easy availability, portability, convenient for use, the best osteogenesis, besides, its suitability for different categories of war injury bone defect, and its plasticity and cohesiveness, the latter is very important for improving the level of war injury cure. Recently, bone graft materials can be roughly grouped into two categories, ie , biomaterials and artificial materials. In practice, many different materials are offered for our selection, which have their own respective advantage and disadvantage, so it is advisable for us to combine over two different materials to make up with some satisfied end-product. Decalcified bone matrix(DBM)boasts of good osteogenesis, easily harvested in large quantity, convenient for preservation and portability,aand also the good bone transduction, all the above merits contribute to its successful clinical utilization in treating bone defect and nonunion as a substitute of former autograft practice; Calcium Phosphate cement(CPC), also called hydroxyapatite cement(HA), is a bioactive new-typed non-ceramic hydroxyapatite artificial material; N butyl cyanoacrylate (NBCA) is a bone adhesive current inclinical use.In this research, the DBM particles were synthesized by our own on the basis of referring to related published literature; besides, following the principle of tissue engineering, the DBM particles were integrated into Calcium Phosphate cement(CPC) with appropriate addition of NBCA. The end-product of this procedure is a compound bone cement(DCN), with the advantages of good bone induction and transduction, biodegradability, fast solidification and high intensity. For studying its feasibility in clinical practice, a series of research works were undergone , including chemical and physical features, biocompatibility, osteogenesis, and experiment of animal segmental bone defect repair; through the above endeavors, we hope to locate a new-typed and ideal bone repair material for both the peace and war-time bone defect repair.1. Constructive and biomechenical properties of material of DCN bone cementsUnder scanning electron microscope(SEM), the CPC was found to be well-distributed between DBM particles and covered the surface of DBM with honeycomb-like state where have a large quality of cave in 30-60 n m size. The DBM particles with irregular gaps existing within interspace were connected with CPC by the multipolar mode in the compound materials, this provide a good condition for newly formed bone fill in; The results of mechanical measurement show the ultimate compressive strengths of DCN bone cements were 43.3Mpa, slightly lower than PMMA (P<0.01) ,but obsviously higher than CPC (PO.01) ,this indicated that the DCN bone cement have a good strengths. Compared with CPC, DBM, NBCA, the FTIR results of DCN bone cements show that no new bond arise, it suggest that there are interaction among CPC, DBM and NBCA, but this did not change the special bond of each material, as a results, did not influence the osteoinduction of DBM.2. Biocompatibility and biological safety evaluation of DCN bone cementBiocompatibility and biological safety of DCN bone cement were evaluatedby a series of in vitro and in vivo studies including animal experiments, and histochemical detection to test the toxicity, pyrogen, coagulant, hemolysis and immunogen. The bone cement was found to have no toxicity and no pyrogen in animal test, no hemolytic activities and it couldn't influence the blood coagulation in vitro. Implanted the bone cement into the muscle pouches in the thigh of mice or rabbits, it was found no obvious specific antibodies produced in serum and no significant immune reaction of foreign body. All the results indicated tha...
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