An Original Trabecular Bone Mimic Porous Tantalum Scaffold For Bone Defect In Bone Tissue Engineering

OBJECTIVE: To investigate the biocompatibility and osteogenic properties of a novel trabecular bone mimic tantalum scaffold for bone tissue engineering,and verify the effect of bone defect repair.Materials and Methods: Designed and manufactured novel three-dimensional multi-scale interconnects(trans-scale-independent but interconnected)porous tantalum.The morphology of the novel porous tantalum was observed using scanning electron microscope(SEM)and industrial computer tomography(CT).Mesenchymal stem cells(MSCs)were cultured with novel porous tantalum,SEM was applied for the observation of cell morphology and adhesion.MTT methods were used to evaluate the cytotoxicity of porous tantalum and its effect on cell proliferation.Observation of the Effect of Porous Tantalum Material on Calcium Salt Deposits of Human Mesenchymal Stem Cells by Alizarin Red Staining.A canine femoral shaft bone defect model was established,and an original porous tantalum rod was used to repair the bone defect.Repair effects and bony integration were evaluated by hard tissue sliceexamination and push-out tests at indicated time.Results: The original porous tantalum is trabecular bone mimic,and has the characteristics of three-dimensional,multi-scale and interconnection.MSCs adhere to the surface of tantalum and proliferate over time.Porous tantalum has no cytotoxic effect on MSCs and has positive effect cell proliferation probably.Alizarin red staining showed that the new porous tantalum did not affect the osteogenic induction effect in vitro.In the bone defect model,the porous tantalum rod was tightly connected to the host bone,and new bone was observed at the tantalum-host bone interface within 3 and 6 months after implantation.Favorable bone ingrowth was observed in the central of the tantalum rod.The push-out test showed that the strength needed to push out the tantalum rod is comparable in both 3 months and 6 months when compared with the normal femoral shaft bone tissue.Conclusion: These findings suggested that the novel trabecular bone mimic porous tantalum scaffold is biocompatible and osteoinductive,which hold the potential for use in bone tissue engineering.