Tóm tắt

Large bone defects remain a worldwide healthy problem needing to be solved. 3D printed tantalum (Ta) scaf-folds have enormous potential to repair bone defects and have applied in clinic in recent years. Although thernporous structure of 3D printed Ta scaffolds could allow bone ingrowth, the surface property that reactive withrnsurrounding tissue is still unfavorable and thus the early osteointegration is impeded. Magnesium (Mg), a ne-cessary element during bone development, has been reported with effectively osteogenesis and angiogenesisrncapacity. Hence, in this study, three concentrations of Mg were doped on the surface of 3D printed tantalumrnscaffolds utilizing the surface adhesion ability of polydopamine (Ta-PDA-Mg) to improve its surface bioactivity.rnThe physiochemical property of resultant Ta-PDA-Mg scaffold was characterized and their osteogenic and an-giogenic effects were tested through a serial of experiments bothin vitro andin vivo. Results show that Ta-PDA-Mg2 possessed the highest ion release, and all scaffolds showed excellent biocompatibility. The adhesion, an-giogenesis and osteogenesis were all improved in Mg doping groupsin vitro, while the Ta-PDA-Mg2 exhibited thernbest performances. Then thein vivo performance was examined through rat femur condyles bone defect model.rnResults demonstrate that the Ta-PDA-Mg2 significantly enhanced the vascularized bone formation and the os-teointegration, which was further confirmed through pull out test. Therefore, Mg doped 3D printed Ta scaffoldrncould improve surface bioactivity and lead to better osteogenesis and angiogenesis, which may provide novelrnstrategy to develop bioactive customized implants in orthopedic applications.