Experimental Study On The Combination Of Bone Marrow Stromal Cells And Platelet-rich Plasma In Repairing The Bone Defect Around The Dental Implant

Objective To induce mandibular bone regeneration and repair the bone defects around the implants using the bone marrow stromal cells combined with platelet-rich plasma and evaluate their osteogenic potential. Provide the experimental basis to find the repairing material for the bone defect around the dental implant.Methods Six healthy adult Beagle dogs were divided into three groups with the completely random method. The animal experiment models were established by extract the bilateral mandibular eight premolars. After one month we checked the dog,s marrow and cultured the BMSCs by adherent culture. As induced to osteoblast, we compounded the cells withβ-tricalcium phosphate (β-TCP), platelet-rich plasma(PRP) respectively. Four BLB 4×10mm implants were separately implanted in each side of the mandibular edentulous areas. At the same time we manufactured the 4×4×5mm size bone defect near each implant,s mesial zone. The defects were implanted with graft materials as follows: BMSCs / PRP composite gel, autogenous bone ,BMSCs /β-TCP compounds and blank control(defect only). The three groups of dogs were then sacrificed at the end of 4, 8 and 12 weeks after operation, and the new bone formation of the experimental group and the control group in diffenent periods of time was observed by means of general observation, X-ray examination, environmental scanning electron microscope observation and histological detection, as well as the osseointegration situation between the new bone and implant.Results There were varying degrees bone regeneration in all experimental groups 4,8,12 weeks after operations, while only a small amount of bone regeneration in the control group. Theβ-TCP was gradually absorbed which compounded in the BMSCs /β-TCP implanted in the defect area, but there were still residues after 12 weeks. But the BMSCs / PRP materials were absorbed completely which were implanted in the defect areas in the different periods, and the new bone was higher than the other 3 groups.As well as the osseointegration between the new bone and implant was significantly higher than the other 3 groups by the environmental scanning electron microscope observation.Conclusions (1) As the seed cells of bone tissue engineering BMSCs can be directional induced to osteoblast, and to promote bone formation.(2) With the three elements of seed cell, scaffold material and growth factor and good biocompatibility, BMSCs / PRP can be the tissue-engineered composite gel. They can promote the new bone formation in the peri-implant bone defect as well as promote the implant osseointegration, which have shortened the time of implant osseointegration. (3)With the great tissue regeneration ability the autologous BMSCs and PRP can be transplanted to self and overcome immunogenicity and the spreading of disease of allograft. So we have the experimental base for clinical application that the tissue engineering can be a very good method to repairing the bone defect around the implant.