Experimental Study Of The Shaped Titanium Mesh Combined With Autogenous Particulate Bone Graft And Simultaneous Implant For Reconstructing Segmental Mandibular Defect

For the purpose of studying the feasibility of the operation that using shaped titanium mesh combined autogenous particulate bone graft and simultaneous implant to reconstruct the segmental mandibular defect, we firstly observed the bone formation and the turnover of autogenous particulate bone grafts in the shaped titanium mesh. Additionally we studied the contribution of the simultaneous implant to the healing of the autogenous particulate bone graft and its osseointegration. Our results showed the contour of the reconstructed mandible was satisfactory and its function was excellent. The ossific fusion among the particulate bone grafts was fine, as well as the bone structure was good. All implants showed excellent osseointegration with around bone graft. There was a trend that simultaneous implant could optimize the structure of the grafted bone nearby.PartⅠExperimental study of the shaped titanium mesh with autogenous particulate bone graft for reconstructing segmental mandibular defectObjective: To investigate the formation and turnover of the bone graft as using the shaped titanium mesh with autogenous particulate bone grafts to reconstruct the segmental mandibular defect.Methods: Five Beagle dogs were prepared with unilateral 3.5cm segmental mandibular defect. Titanium mesh was shaped according to the mandibular defect and was fixed with titanium screws to reconstruct mandibular defects. The ablated mandibular bone and iliac bone were crashed into approximately 2mm particulates and then filled into the titanium mesh tightly(cortical bone: cancellous bone≈3:1). X-ray films, SEM, and histological sections of the reconstructed mandibles were used to evaluate the bone healing and bone formation of the grafted bone in the animals after 6 months.Results: The contour of the reconstructed mandible was satisfactory and its function was excellent. The ossific fusion among the particulate bone grafts was fine, as well as the bone structure was good. The bone density of healing grafted bone was high and no resorption was found while accompanied by ossific healing in the reconstructed mandible.Conclusion: The ossific fusion among the particulate bone grafts in the shaped titanium mesh was fine. The reconstructed mandible has excellent function, and can provide enough width and height of the alveolar for prostheses and implantation.PartⅡContribution of the simultaneous implant on the healing of the autogenous particulate bone graftObjective: To observe the effect of the simultaneous implantation on the healing of the autogenous particulate grafted bone.Methods: The operation was described as the PartⅠ. The dogs were sacrificed after six months. SEM, EDS, and histological sections were used to evaluate the simultaneous implant to the healing of the autogenous particulate bone graft.Results: All implants showed excellent osseointegration with around bone graft. Bone near the implant was more compact than the bone away from it. The contents of calcium and phosphor in cancellous bone were lower than the cortical bone and the graft bone regardless of the bone near or distant to the implant. However, no difference of the contents of calcium and phosphor were noted among the three bones. Conclusion: Simultaneous implants showed excellent osseointegration with the autogenous particulate bone graft in the titanium mesh. It dose not interfer the mineralization of the bone graft, but has a trend of promoting optimization of the structure of the grafted bone nearby.