Experimental Study Of Using Platelet-rich Fibrin In The Regeneration Of Bone Defects Around Immediate-implant And Immediate-loading Implant

Objective To observe the growth of new bone around the implant after platelet-rich fibrin were used in the animal model of bone defects around immediate-implant and immediate-loading implant. Further more, to explore the possible bone regeneration mechanisms initiated by PRF and the promoting effects of Bio-oss in the repair of peri-implant bone defects by using PRF. At last, to provide theoretical evidences and experimental information for the clinical application..Material and Methods Four male adult Beagle dogs were undergone extraction of the bilateral mandible fourth premolar to create edentulous regions. Each mandible of the dogs was implanted one titanium cylindrical screw threaded implant respectively after the extraction surgery. The implant superstructures were installed immediately after implant surgery in order to ensure the immediate loading. Then a mandible defect (7.0mm×3.0mm) was created in the buccal ridge of the implant. Self-controlled design was applied in this experiment. PRF/Bio-oss was filled in the defect of the experimental side and Bio-oss was filled in the control side.3months after operation, the location and formation of new bone was observed, and measured and recorded, at the same time, bilateral buccal bones of implants were cut and HE sections were prepaired and observed by microscope.Results The mean±standard deviation of the increased height of the buccal bone were3.25±0.56mm in the experimental group and1.88 ±0.48mm in the control group. The mean±standard deviation of the increased buccal defect area were15.38±0.97mm2in the experimental group and13.31±0.72mm2in the control group. A greater volume of new bone formation were observed in the experimental group which received PRF than in the control group (P<0.05).The new bone formation was more and the osteoblasts was richer and more maturity in the buccal of implant in experimental group in histological sections.Conclusion PRF can promote the regeneration of bone defects around immediate-implant and immediate-loading implant. PRF can pacilitate the effects of Bio-oss in the repair of peri-implant bone defects.