Experimental Study Of Allograft Of Radiated Bone Incoporated With Norfloxacin And Siver

Objective: To observe the effect of repairing segmental bone defect with allograft of radiated bone incorporated with norfloxacin and silver.Method: A segmental bone defect(1×1cm2) models were created at skull parietal bone in 48 NanChang rabbits.They were randomly divided into the four groups on average,the bone defect was filled by the radiated allogeneic bone incorporated with norfloxacin and silver(RABNS)group(Group A),radiated allogeneic bone group(Group B),deep-frozen allogeneic bone group(Group C) and autogeneic bone group(Group D).The bacteriostatic effect and Ag＋ level were detected in vitro,the effect of repairing defects was observed by Immunologic property ,Radionuclide bone imanging and Histologic studies respectively.Results: (1),No bacterial growth was investigated in bone grafts of Group A,B,C. By contrast, bone grafts of Group A could effectively inhibit growth of bacteria (P<0.01). (2),The contents of Lymphocytoxicity showed no difference among different groups at 4th,8th,12th weeks postoperatively.(3),The radioactivities were increased postoperatively,and were stable in the 8th,12th week. The radioactivity showed higher in Group D than in Group A,B,C(P<0.05),But it was no significant among different groups in the 8th,12th week(P>0.05),and the changes of radioactivity were consistent with that of histology.(4),The bone information of bone allografts was similar to that of bone autografts,the processes of bone-healing was from united end to the bone grafts,from periphery to the center ,and from Haversian cannals to its periphery.Conclusion: RABNS can avoid contamination ,and the infection and cross-infection of the bone allograft.It has low antigenecity,good osteogenic ability,and has important clinical meaning in treatmeat of the segmental bone defects.