J. Mater. Sci. Technol. ›› 2023, Vol. 135: 186-198.DOI: 10.1016/j.jmst.2022.06.036

• Research Article • Previous Articles     Next Articles

Enhancement of critical-sized bone defect regeneration by magnesium oxide-reinforced 3D scaffold with improved osteogenic and angiogenic properties

Bo Chena,d, Zhengjie Linb, Qimanguli Saidinga, Yongcan Huangc, Yi Sund,e, Xinyun Zhaif, Ziyu Ningg, Hai Liangh, Wei Qiaoi, Binsheng Yuc,*, Kelvin W.K. Yeungd,e,*, Jie Shenc,d,e,*   

  1. aDepartment of Orthopaedics, Shanghai Key Laboratory for Prevention and Treatment of Bone and Joint Diseases, Shanghai Institute of Traumatology and Orthopaedics, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200 25, China;
    b3D Printing Clinical Translational and Regenerative Medicine Center, Shenzhen Qianhai Shekou Free Trade Zone Hospital, Shenzhen 518067, China;
    cShenzhen Key Laboratory of Spine Surgery, Department of Spine Surgery, Peking University Shenzhen Hospital, Shenzhen 518036, China;
    dDepartment of Orthopaedics and Traumatology, the University of Hong Kong, China Hong Kong Special Administrative Region, China;
    eShenzhen Key Laboratory for Innovative Technology in Orthopaedic Trauma, the University of Hong Kong Shenzhen Hospital, Shenzhen 518053, China;
    fSchool of Materials Science and Engineering, Nankai University, Tianjin 300071, China;
    gDepartment of Pathology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, China;
    hDepartment of Stomatology, Shenzhen Qianhai Shekou Free Trade Zone Hospital, Shenzhen 518067, China;
    iApplied Oral Sciences and Community Dental Care, Faculty of Dentistry, the University of Hong Kong, China Hong Kong Special Administrative Region, China;
    jChina Orthopaedic Regenerative Medicine Group (CORMed), Hangzhou 310000, China
  • Received:2022-01-27 Revised:2022-05-02 Accepted:2022-06-14 Published:2023-02-01 Online:2022-07-24
  • Contact: *E-mail addresses: hpyubinsheng@hotmail.com (B. Yu), wkkyeung@hku.hk (K.W.K. Yeung), jayjayson909@gmail.com (J. Shen)

Abstract: The healing of critical-sized bone defects (CSD) remains a challenge in orthopedic medicine. In recent years, scaffolds with sophisticated microstructures fabricated by the emerging three-dimensional (3D) printing technology have lighted up the treatment of the CSD due to the elaborate microenvironments and support they may build. Here, we established a magnesium oxide-reinforced 3D-printed biocomposite scaffold to investigate the effect of magnesium-enriched 3D microenvironment on CSD repairing. The composite was prepared using a biodegradable polymer matrix, polycaprolactone (PCL), and the dispersion phase, magnesium oxide (MgO). With the appropriate surface treatment by saline coupling agent, the MgO dispersed homogeneously in the polymer matrix, leading to enhanced mechanical performance and steady release of magnesium ion (Mg2+) for superior cytocompatibility, higher cell viability, advanced osteogenic differentiation, and cell mineralization capabilities in comparison with the pure PCL. The in-vivo femoral implantation and critical-sized cranial bone defect studies demonstrated the importance of the 3D magnesium microenvironment, as a scaffold that released appropriate Mg2+ exhibited remarkably increased bone volume, enhanced angiogenesis, and almost recovered CSD after 8-week implantation. Overall, this study suggests that the magnesium-enriched 3D scaffold is a potential candidate for the treatment of CSD in a cell-free therapeutic approach.

Key words: 3D printing, Magnesium, Critical-sized defect, Bone regeneration, Angiogenesis, Scaffold