Reconstruction of caprine mandibular segmental defect by tissue engineered bone reinforced by titanium reticulum

Objective: To investigate the feasibility of using natural poritos as scaffolds in bone tissue engineering (TE) and repair of caprine mandibular segmental defect with titanium reticulum reinforced. Methods: Natural poritos with a pore of 190-230 μn in size and porosity of about 50% -65% was molded into the shape of granules 5 mm×5 mm×5 mm in size. Expanded autologous caprine marrow mesenchymal stem cells were induced by recombinant human morphogenetic protein-2 ( rhBMP2 ) to improve osteoblastic phenotype. Then marrow derived osteoblasts were seeded into poritos in density of 4×107/ml and incubated in vitro for 48 hours prior to implantation. Then osteoblastic cells/poritos complexes were implanted into mandibular defect and the defect was reinforced by titanium reticulum. Implantation of poritos alone acted as the control. Bone regeneration was assessed 4, 8, 16 weeks after implantation using roentgenographic analysis and histological observation was done after 16 weeks. Results: New bone could be observed histologically on the surface and in the pores of natural coral in all specimens in the cell-seeding group, whereas in the control group there was no evidence of osteogenesis process in the center of the construction. The results showed that new bone grafts were successfully restored 16 weeks after implantation. Conclusions: This study suggests the feasibility of using porous coral as scaffold material transplanted with marrow derived osteoblasts by TE method. By means of titanium reticulum reinforcement, mandibular defect could be successfully restored. It shows the potentiality of using this method for the reconstruction of bone defect in clinic.