The driving force behind the development of bioresorbable metals is primarily due to their ability to provide metal-like mechanical properties while degrading safely in the body.
[1] This is especially relevant in orthopaedic applications, where although many surgeries only require implants to provide temporary support (allowing the surrounding tissue to heal), the majority of current bio-metals are permanent (e.g. stainless steel, titanium).
Degradation of the implant means that intervention or secondary surgery will not be necessary to remove the material at the end of its functional life, providing significant savings in both cost and time for the patient and health care system.
Bioresorbable metals are able to withstand loads that would destroy any currently available polymers, and offer much greater plasticity than bioceramics, which are brittle and prone to fracture.
A well-designed implant could provide the exact mechanical support needed for different areas (through alloying and metal working), and load would be transferred to the surrounding tissue over time, letting it heal and reducing the effects of stress shielding.
It was not until the late 1990s that interest started to pick up again, Mg has a density close to that of bone and is absorbed by the body .Mg is of interest for orthopedic applications due to its relatively low cost, high specific strength, and near-bone elastic modulus, which avoids stress shielding and allows uniform distribution of tissue stress [14][15] Currently, most research on Mg is focused on reducing and controlling the rate of degradation, with many alloys corroding too rapidly (in vitro) for any practical application.