Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, Guangdong Provincial Key Laboratory of Medical Biomechanics, School of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China; Department of Orthopedics, Xinhui People's Hospital, Southern Medical University, Xinhui 529100, China; Department of Orthopedics, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China; Laboratory of Basic Medicine, General Hospital of Southern Theater Command of PLA, Guangzhou 510010, China.
Department of Orthopedics, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China; The Second School of Clinical Medicine, Southern Medical University, Guangzhou 510515, China.
Mater Sci Eng C Mater Biol Appl. 2020 Dec;117:111303. doi: 10.1016/j.msec.2020.111303. Epub 2020 Jul 28.
Large bone defects remain a worldwide healthy problem needing to be solved. 3D printed tantalum (Ta) scaffolds have enormous potential to repair bone defects and have applied in clinic in recent years. Although the porous structure of 3D printed Ta scaffolds could allow bone ingrowth, the surface property that reactive with surrounding tissue is still unfavorable and thus the early osteointegration is impeded. Magnesium (Mg), a necessary element during bone development, has been reported with effectively osteogenesis and angiogenesis capacity. Hence, in this study, three concentrations of Mg were doped on the surface of 3D printed tantalum scaffolds utilizing the surface adhesion ability of polydopamine (Ta-PDA-Mg) to improve its surface bioactivity. The physiochemical property of resultant Ta-PDA-Mg scaffold was characterized and their osteogenic and angiogenic effects were tested through a serial of experiments both in vitro and in vivo. Results show that Ta-PDA-Mg2 possessed the highest ion release, and all scaffolds showed excellent biocompatibility. The adhesion, angiogenesis and osteogenesis were all improved in Mg doping groups in vitro, while the Ta-PDA-Mg2 exhibited the best performances. Then the in vivo performance was examined through rat femur condyles bone defect model. Results demonstrate that the Ta-PDA-Mg2 significantly enhanced the vascularized bone formation and the osteointegration, which was further confirmed through pull out test. Therefore, Mg doped 3D printed Ta scaffold could improve surface bioactivity and lead to better osteogenesis and angiogenesis, which may provide novel strategy to develop bioactive customized implants in orthopedic applications.
大骨缺损仍然是一个全球性的健康问题，需要解决。3D 打印钽（Ta）支架具有修复骨缺损的巨大潜力，近年来已在临床应用。尽管 3D 打印 Ta 支架的多孔结构可以允许骨长入，但与周围组织反应的表面性能仍然不理想，从而阻碍了早期的骨整合。镁（Mg）是骨骼发育过程中必需的元素，据报道具有有效的成骨和血管生成能力。因此，在这项研究中，利用聚多巴胺（Ta-PDA-Mg）的表面粘附能力，在 3D 打印 Ta 支架的表面掺杂了三种浓度的 Mg，以提高其表面生物活性。对所得 Ta-PDA-Mg 支架的理化性能进行了表征，并通过一系列体外和体内实验测试了其成骨和血管生成效果。结果表明，Ta-PDA-Mg2 具有最高的离子释放量，所有支架均表现出良好的生物相容性。体外实验中，Mg 掺杂组的粘附、血管生成和成骨作用均得到改善，而 Ta-PDA-Mg2 表现出最佳性能。然后通过大鼠股骨髁骨缺损模型检测体内性能。结果表明，Ta-PDA-Mg2 显著增强了血管化骨形成和骨整合，通过拔出试验进一步证实了这一点。因此，掺杂 Mg 的 3D 打印 Ta 支架可以提高表面生物活性，从而促进更好的成骨和血管生成，这可能为骨科应用中开发具有生物活性的定制植入物提供新策略。
