ABSTRACT
[ABSTRACT]AIM:Toinvestigatetheapplicabilityanddegradabilityoftheantigen-extractedxenogeneicbone carrying recombinant human bone morphogenetic protein 2 ( rhBMP-2) as a scaffold in repairing the mandibular defect in vivo.METHODS:New Zealand rabbits (n=28) with 28 mandibular defects were divided into 3 groups at random:anti-gen-extracted xenogeneic cancellous bone /rhBMP-2 group (group A), antigen-extracted xenogeneic cancellous bone group ( group B ) and blank control group ( group C ) .Twelve bone defects each in group A and group B were classified into 3 time points (4, 8 and 12 weeks).Observation in general, X-ray test and hematoxylin and eosin staining and bone density measurement were conducted on each rabbit in group A and group B .Four bone defects were classified into group C .Ob-servation in general , X-ray test and hematoxylin and eosin staining were also conducted on each rabbit in group C .RE-SULTS:The X-ray showed that the implanted materials were degraded after a period of time , and were replaced by autoge-nous bone.At the 12th week, the implanted materials in group A were entirely degraded and replaced by autogenous bone . The bone density measurement showed that the bone density was enhanced after implantation .At the 12th week, there was an obvious difference between group A and group B .The hematoxylin and eosin staining showed there were more neovascu-larization, new fibrosis and new bone formation in group A than those in group B .The implanted material in group A de-graded much faster than that in group B .The significant difference in the new bone area ratio between the 2 groups among all weeks was observed .CONCLUSION: An antigen-extracted xenogeneic cancellous bone has good biocompatibility , which can act as a scaffold in bone repairment .It is the carrier of rhBMP-2 to continue the bone formation .Therefore, anti-gen-extracted xenogeneic cancellous bone is a kind of good material for bone repairment .