Effects of Demineralized Dentin Matrix Used as an rhBMP-2 Carrier for Bone Regeneration

The purpose of this study was to evaluate the DDM as a carrier of recombinant human BMP-2 (rhBMP-2). In the study 1, the rhBMP-2 was fixed to inorganic bovine bones, tricalcium phosphate (TCP), DDM powder, and DDM chip. Over a period of 36 days, the amount of rhBMP-2 released was analyzed. In the study 2, the expression of protein markers by rhBMP-2 combined with DDM was evaluated in mice at 1, 2 and 4 weeks. In the control group (n=20 mice), 20 μg grafts of TCP+rhBMP-2 (concentration=0.05 mg/ml) were applied, while in the experimental group (n=20 mice), 20 μg grafts of DDM powder+rhBMP-2 (concentration=0.05 mg/ml) were applied. In the study 1, the slow release of rhBMP-2 was exhibited by all four graft types throughout the 36-day, a statistically significant large amount of rhBMP-2 was released from the DDM powder compared to the other materials (p<0.05). In the study 2, the expression of osteonectin was found to be limited to adjacent areas of TCP in the control group, however, it was observed in the DDM in the experimental group. The experimental group exhibited significant mature bone formation in the 4th week, but not in the 1st week of the experiment. Within limited research in this study DDM powder appears to have great potential as an effective scaffold for rhBMP-2. In the DDM powder+rhBMP-2, new bone formation was evidently shown and the amount of released rhBMP-2 was the highest. It was proposed that DDM powder might be an effective carrier of rhBMP-2.