Objective To investigated the biological procedure of allograft decalcified bone matrix(DBM)and bone cement(BC)combined with bovine bone morphogenetic protein (bBMP)used for the repair of femoral defect caused by microwave－induced hyperthermia in dogsby 99mTc－MDP bone scintigraphy.Method The canine femoral defect(length 25mm,width 10mm)was caused by microwave－induced hyperthermia(50℃,20minutes)and the composite material was implanted .Then the canine femurs were examined by 99mTc－MDP bone scintigraphy respectively at different postoperative time and the results were compared with that of X－ray photography and histological observation.Bone cement was implanted in the other femur as a contrast.Results It could be observed at the first and the second month that the radioisotope was gathered in the place where the composite material was implanted and the amount of radioisotope gathered in was the most abundant at the third month and it was lasted to the fourth month. That of the sixth month was decreased to that of the second month.The radiation count of the first, the second, the third the fourth and the sixth month were 93.9±12.7, 110.7±16.4,222.1±24.0,201.3±26.9 and 111.6±20.7 respectively,and the count of the third month and the fourth month were more than that of the first, the second and the sixth month(P<0.01).Conclusion The composite material could be remodeled easily and the new bone could be formed by the induction of bBMP. So it could be merged with the normal bone.While the 99mTc－MDP bone scintigraphy is the object and reliable index to determine the biological procedure of the composite material in dogs. Objective To investigated the biological procedure of allograft decalcified bone matrix (DBM) and bone cement (BC) combined with bovine bone morphogenetic protein (bBMP) used for the repair of femoral defect caused by microwave-induced hyperthermia in dogsby 99mTc-MDP bone scintigraphy. Method The canine femoral defect (length 25mm, width 10mm) was caused by microwave-induced hyperthermia (50 ° C, 20minutes) and the composite material was implanted .Then the canine femurs were examined by 99mTc-MDP bone scintigraphy respectively at different postoperative time and the results were compared with that of X-ray photography and histological observation. Bone cement was implanted in the other femur as a contrast. Results It could be observed at the first and the second month that the radioisotope was gathered in the place where the composite material was implanted and the amount of radioisotope gathered in was the most abundant at the third month and it was lasted to the fourth month. That of th e sixth month was decreased to that of the second month. The radiation count of the first, the second, the third fourth and the sixth month were 93.9 ± 12.7, 110.7 ± 16.4, 222.1 ± 24.0, 201.3 ± 26.9 and 111.6 ± 20.7 respectively, and the count of the third month and the fourth month were more than that of the first, the second and the sixth month (P <0.01) .Conclusion The composite material could be remodeled easily and the new bone could be formed by the induction of bBMP. So it could be merged with the normal bone. Whilst the 99mTc-MDP bone scintigraphy is the object and reliable index to determine the biological procedure of the composite material in dogs.