An Experimental Study Of Parathyroid Hormone (1-34) Combined With Guided Bone Regeneration In The Treatment Of Periodontal Bone Defect

Objective:Through the establishment of periodontal bone defect model in rats,the use of parathyroid hormone(1-34)combined with guided bone tissue regeneration to repair periodontal defects of bone lesions,and analyzed using the PTH(1-34)the therapeutic effect of combined guided bone tissue regeneration.Methods:36 healthy SD male rats were selected to establish an experimental animal model of maxillary periodontal defect.The experimental animals were randomly divided into groups A,B,C and D,with 9 in each group.Group A(control group,no GBR no PTH),group B(with GBR no PTH),group C(no GBR with PTH),group D(with GBR with PTH),Group C and D were injected with PTH on the following day,with a dose of 20μg/kg and 3 times/week,Group A and group B were given the same dose of physiological saline.Three animals were executed in 2 weeks,4 weeks and 8 weeks after surgery,and the maxillary specimens were taken for general,CBCT and histological observation.Results: 1.In the 2,4 and 8weeks after surgery,no obvious and obvious periodontal bags were found in each group of bone defects,but in comparison with the preoperative period,there was obvious gingival withdrawal(P<0.05)in the bone defect area of group A and group C.2.CBCT showed that the density in the control group and group C showed no significant change in the defect area,and showed a low density penetrative projection,and bone absorption in the periphery of the alveolar bone around the defect area,Group B,group D bone defect area did not see a significant decrease of the alveolar height,density were higher than the control group,and group D bone defect area is the continuity of bone tissue is superior to group B,4 weeks after surgery can be observed in mature newborn bone tissue.3.Histological observation found that the more active group D defect area during the period of development,4 weeks after surgery can observe strip new bone tissue,osteoblastactivity,show pleomorphism,obvious bone sag,mature collagen fiber structure.New bone defect,and the growth of group C the edge of osteoblast proliferation,active osteoblast cube,arranged along the surface of new bone,new trabecular bone density than control group and neatly.Conclusion:Intermittent injection of PTH(1-34)combined to guide bone regeneration can promote the regeneration of bone tissue in periodontal bone defect,accelerate the regeneration rate of early bone tissue and shorten the healing period after periodontal defect.