Effects Of Nerve Growth Factor And Bio-Oss Mixture On Bone Defect Healing

ObjectiveTo manufacture a transplantation with nerve growth factor and anorganic bovine bone (Bio-Oss) mixture to repair defect of rat tibia bone, and to observe whether the mixture can promote bone formation.Methods48male SD rats (weight from220to250g) were randomly divided into3groups, each group contain16rats. A3mm bone defect on the left rat tibia bone was established in all groups. NGF/Bio-Oss mixture were implanted into the defects as experiment group, Bio-Oss with physiological saline were implanted into the defects as control group, and the defects without any implant as untreated group. Then randomly sacrificed8rats respectively from each group at4weeks and8weeks after transplantation. Osteoplastic situation at two time point was observed by X-ray, cell morphology observation and BMP-2immunohistochemistry examination.Results1.4weeks:Generally anatomy observation:newly formed bone in the experiment group at were more than the other groups. Cell morphology observation:the new trabecular and osteoblsts in the experiment group were more mature compared with the other groups at4weeks, and there were more new blood vessel in the experiment group. Mean of BMP-2immunohistochemistry examination revealed that BMP-2proteins presented in the subperiosteum and around the trabecular bone, and distributed in osteoblasts and immature bone cells. The expression of BMP-2in the experiment group were higher than the control group, the difference was significant statistically (P<0.01). The expression of BMP-2in the untreated group wwew the lowest, there was statistically significant difference with the other groups (P<0.01).2.8weeks:Generally anatomy observation: All the bone defect were agglutinated at8weeks, colour or hardeness of new bone in the experiment group approached to the adjacent host bone. X-ray observation:bone density in the experiment group and the control group were approached to the adjacent host bone at8weeks, and the outline of new bone were almost agree with the original bone. Bone density in the untreated group were slightly lower than the other groups, and have bone defect incisure.Cell morphology observation:All bone defects at were filled with new bone, while maturation of the center on new bone in the untreated group is the lowest.ConclusionNerve growth factor and Bio-Oss mixture could accelerate bone formation, increase bone mass, promote bone maturity and shorten healing time in bone defects of rat tibia.