Surface modification techniques of magnesium-based alloys for implant applications

Biodegradable materials like magnesium-based alloys are widely employed for making implants. Mg-based alloys show good biocompatibility, biodegradability, and mechanical properties similar to bone material unlike other commonly used implant materials, i.e., stainless steel, titanium, and Co-Cr alloy, which have negligible degradation rates and require revision surgery for the removal of the implant. Magnesium alloy-based implant has high degradation rates and avoids the need for a second surgery. But high degradation rates and poor mechanical properties in magnesium alloys also pose a challenge to their use as implant material. In the absence of controlled degradation, they can degrade completely before serving their intended purpose in the human body. Several surface modification techniques are used to control the degradation rates. Surface coating is one of the methods of surface modification. This paper discusses various types of surface coating techniques for magnesium-based alloys. This paper also discusses the future scope of surface technology of magnesium-based implant materials.