[Preparation and osteogenic activity of combining XXXX cement with bone morphogenetic protein composite as a bone graft material].

@entity19 @entity78 @entity4411 @entity4653
OBJECTIVES: To construct new type of bone graft material by combining @entity78 cement (CPC) with bone morphogenetic protein (BMP), and then to detect its osteogenic activity. METHODS: The surface of CPC and @entity4411 /BMP composite were observed by @entity4653 ( @entity4653 ). CPC and CPC/BMP pellets were separately implanted into the thigh muscle pouches of @entity19 . Samples obtained at different times were tested by histological analysis, @entity4653 , organic substance detection, and alkaline phosphatase (ALP) measurement to observe the induced ectopic bone formation. RESULTS: Under @entity4653 , the CPC and CPC/BMP composite was found to consist primarily of platy crystals, granular crystals and some small rod-like crystals with micropores about 10-50 microm in size. BMP about 1-5 microm in size was seen like micro globules distributing evenly in the micropores. Newly formed cartilage or bone was not found in the CPC group. In the CPC/BMP group, mesenchymal cells were proliferated and abundant cartilage was found in one week. Woven bone appeared at 2 weeks. New bone formation increased with bone marrow at 4 weeks. At 8 weeks, the implanted CPC/BMP became heterogeneous and a lot of collapsed granules were observed. At the end of 16 weeks, mature lamellar bone appeared and the volume of the implanted CPC/BMP became smaller. One week after implantation, the ALP increased evidently in the CPC/BMP groups and reached the highest level at the 4th week, which was about 168 U/L. The content of organic substance in specimens increased from 22% to 39% by the end of the 16th week, showing the continuous calcification and formation of new bone. @entity4653 also showed that the CPC/BMP composite had good potentiality of ectopic bone induction, and the new bone formed accompanied by the slow degradation of the material. CONCLUSION: The results of this study suggested that the CPC/BMP composite could be used as material for bone graft substitute.
