An Experimental Study On Repairment Of Bone Defect With Compound Material

OBJECTIVE: To analyse the capacity of compound materials of decalcified bone matrix (DBM) particles which were combined with or not with rhBMP-2 impregnated with bone cement for repairment of experimental bone defects. METHODS:To assess the constructive and biomechanical properties , bone inductive and conductive capacities of the compound materials , the methods of biomechanics , histology , intravascular injections of India ink , scan electron microscope (SEM) were used.RESULTS: 1.The constructive properties were observed by SEM and biomechanical properties were measured by Instron mechanical testing machine. Results showed that,DBM particles were connected with bone cement tightly by multipolar mode and irregular gaps with diameter of 100-400 μ m were existed between them,the minimal ultimate compressive strengths were 0 percent DBM in (59.30 ± 2.23)MPa,30 percent in (27.11 ± 1.77)MPa and 40 percent in (19.28 ± 1.62)MPa,the minimal ultimate bending strengths were 0 percent in(54.34 ± 3.74)MPa,30 percent in (18.52 ± 1.11)MPa and 40 percent in (13.28 ± 1.42)MPa.2.The effects of compound materials on the induction of bone formation were investigated in NIH mouse models.It was resulted that in with rhBMP-2 group, mesenchymal cells gathered in implanted material at the 7th day postoperation, chondrogenesis were found at 14 to 21 days after implantation,new bone formation were observed at about 21 to 28 days after surgery,the bone inductive capacity of the group with rhBMP-2 was higher than the gorup not with rhBMP-2.3.Studies on repairment of segmental bone defects with the compound materials were investigated in New Zealand rabbit models.lt was shown that, at the second week the inflammatory cells reaction was less...