Advanced Platelet Fibrin Rich To Promote Bone Regeneration In Rabbit Skull

Objective : To know the effect of A-PRF on bone regeneration by establishment of rabbit skull defect models.Method: Thirty animals were randomly divided into the A-PRF group and the blank control group(n=15),a 6.0 mm complete perforative star bone defect was made on each side of calvarial suture,the A-PRF group was implanted with A-PRF membrane and the blank control group was filled nonmaterial,animals were killed on the postoperative day,postoperative 2 weeks,4 weeks,8 weeks and 12 weeks after a general observation,and the bone samples were obtained at each time,the bone samples were subjected to the x-ray,micro CT analysis,Haematoxylin and eosin staining,masson staining and immunohistochemical analysis.Results: Thirty rabbit skull bone defect models were successfully,A-PRF was found to be able to increase the new bone formation,the new bone was obviously after 4 weeks,The new bone gradually mature as the around one after 8 weeks.In the blank control group defect area was filled with soft tissue,no new bone was found till 12 weeks after surgery.X-ray: In the A-PRF group the bone defect was showing with a centripetalthe white high density shadow,in the blank control group a small amount of white high density shadow was showing postoperative 12 weeks.Micro-CT: In the A-PRF group new bone trabecula formated postoperative 2 weeks,with the extension of time,it’s obviously and the arranged regularly.In the blank control group the bone trabecular was fewer,compared the BV/TV,Tb.N,Tb.Th parameter,they were considered statistically significant at the each time compared to the A-PRF group(P< 0.05).HE staining: In the A-PRF group a large number of red blood cells,white blood cells,platelets were seen postoperative day,a closely bone was found postoperative 2 weeks,the bone trabecula was formed postoperative 4 weeks,the bone marrow cavity and bone marrow were seen postoperative 8 and 12 weeks.In the blank control group the defect was filled with soft tissue,a little amount of new bone was seen till postoperative 12 weeks.Masson staining: Much more red area was found in the A-PRF group than the blank control group at the same time.Immunohistochemistry analysis:In the A-PRF group RANKL was stablely released postoperative 2 weeks,then gradually increased till 12 weeks.Which was statistically different from the blank control group(P < 0.05),OPG release gradually increased after the operation,reached a peak and then decreased gradually postoperative 8 weeks,which was statistically different from the blank control group(P < 0.05).In the blank control group RANKL and OPG expression was increased on postoperative 8 weeks,and they were increasing till 12 weeks.Conclusion: 1.The rabbit skull bone defect was successfully established.2.A-PRF was able to induce to the formation of new bone.3.Anatomical observation,X-ray and Micro-CT were indicated that A-PRF could induce the new bone formation with a centripetal growth.4.The A-PRF degradation time was about 4-8weeks.