Advances and Prospects of Biodegradable Magnesium-based Metal Matrix Composites for Biomedical Implants: A Comprehensive Review

Abstract

Magnesium-based biodegradable composites offer significant advantages over nondegradable materials for biomedical implants. These materials degrade gradually in physiological environments, thereby reducing stress shielding and eliminating the need for secondary implant removal surgeries. This review explores how alloying elements (e.g., Zn, Ca, Sr) in the magnesium matrix and reinforcing phases (e.g., hydroxyapatite, SiC, TiC) in metal matrix composites influence degradation kinetics, mechanical integrity, and ion release behaviour. Proper regulation of the degradation rate is critical for maintaining mechanical support during the healing phase while ensuring biocompatibility. This study expands the use of magnesium composites in implantable medical devices. Some examples are orthopaedic implants, circulatory stents, bone fixation devices, and soft tissue scaffolds. The above uses demonstrate the ability of magnesium composites to improve patient outcomes and reduce implant-related procedures through gradual breakdown and tissue regeneration. The review also reports the biodegradation control, biocompatibility, manufacturing scale-up, and regulatory requirements for clinical translation. Successful commercialisation depends on balancing the degradation rate with mechanical support, limiting cytotoxicity, and meeting regulatory standards. In conclusion, magnesium-based biodegradable composites have the potential to revolutionise biomedical implants. The unique combination of mechanical properties, biocompatibility, and regulated biodegradation improves patient outcomes and therapy efficacy. Medical device design and regenerative medicine will benefit from magnesium composites as researchers improve synthesis methods, material properties, and overcome barriers.