Magnesium Based Orthopedic Implants and Controlling the Corrosion Rate

Though magnesium has long been determined potentially effective as an orthopedic biomaterial for implants, the high corrosion rate has been difficult to control. Extensive research has been done on limiting the corrosion rate to extend the viability of orthopedic implants for bone regrowth. In this research, three methods of magnesium corrosion reduction were compared: alloying, surface coating, and magnesium syntactic composite synthesis. Of the aforementioned methods, the syntactic magnesium-hydroxyapatite composite foam shows the most potential. Since the foam is syntactic, the structure relies upon the degradation of magnesium to function. This magnesium corrosion rate can be controlled with alloying techniques on the metal. This gives potential for replacement with natural bone cell as the magnesium dissolves. The foams showed remarkable improvement of mechanical properties over a normal hydroxyapatite structure and has high potential for creating organic structures that promote bone regrowth. Through further testing and successful optimization of these magnesium-hydroxyapatite foam structures, the prospect of calculated corrosion and assisted bone regrowth in magnesium orthopedic implants becomes possible