Next-Generation Biomaterials for Bone-Tissue Regeneration: Mg-Alloys on the Move

Abstract

Disorders related to the bone health are becoming a significant concern due to subsequent rise in ageing human population. It is estimated that more than two million bone-surgeries are performed worldwide with an annual cost of $2.5 billion. In order to replace damaged bone-tissues and restore their function, biomaterials consisting of stainless steels, cobalt-chromium and titanium alloys are implanted. However, these permanent (non-biodegradable) implants often lead to stress-shielding effects and ions release as they interact with the cells and fluids in the body. It is required to overcome these issues by improving the quality of implant materials and increasing their service life. Recently, research in biodegradable materials, consisting of magnesium alloys in particular, has received global attention owning to their biocompatibility and closer mechanical properties to the natural bone. However, due to their rapid corrosion rate in the body fluids, clinical applications of Mg-alloys as viable bone-implants have been restricted. A number of Mg-alloys have been tested since (both in vivo and in vitro) to optimize their biodegradation rare and corrosion properties. The present review summarizes the most recent developments in Mg-alloys designed with biodegradation tailored to the bone-cells growth and highlights the most successful ways to optimize their surface properties for optimum cell/material interaction.