FABRICATION OF VASCULARIZED BONE-GRAFTS USING CERAMIC CHAMBERS

The present study was designed to create a vascularized bone graft com bining the osteogenetic potential of bone marrow cells, and vascular b undle implantation in a hydroxyapatite chamber, using New Zealand whit e rabbits. A hydroxyapatite chamber was molded into a cylindrical shap e, and hydroxyapatite fillers were soaked in an autogenous bone-marrow -cell suspension at a concentration of 1.6 x 10(8)/ml. In one group, t he implant was packed with allogenic demineralized bone matrix powder (DBM) and implanted in the mid-thigh subcutaneously, with the epigastr ic vessels running through the chamber. In a second group, the chamber with bone marrow cells and DBM was implanted subcutaneously, without vascular bundle implantation. The control group consisted of a chamber without DBM, soaked in venous blood and implanted in the opposite thi gh, with the epigastric vessels running through the chamber. Cross-sec tional bone area and mineral apposition rate were measured, in additio n to newly-formed vessels. After 3 weeks, chambers implanted with bone marrow cells and DBM demonstrated consistent bone formation in the po res of the chamber walls and within the chambers. No evidence of bone formation was noted in the chambers soaked with venous blood. The resu lts indicated that vascular-bundle implantation promoted earlier bone formation with neovascularization in the chambers with bone-marrow cel ls and DBM. Microangiograms revealed vascular connections between the vascular bundle and soft tissue surrounding the chamber through newly- formed vessels in the chamber wall. These findings support the concept of creating a preformed vascularized bone graft, to reconstruct segme ntal bone defects.