Abstract
Mg and its alloys degrade under physiological conditions. The great challenge here is to tailor the degradation in a manner that is suitable for a biological environment. Fast or uncontrolled corrosion is associated with strong hydrogen and ion release and severe pH changes, which can lead to a fast loss of mechanical stability and undesirable biological reactions. Since these processes are highly complex in a living system and sufficient data describing the degradation in vivo is missing, it is very difficult to produce knowledge based new alloys. Still, the endeavour is successful: one CE certified Mg-alloy compression screw (Magnezix, Syntellix AG, Germany) and a Mg-based drug-eluting stent (Magmaris, Biotronik AG, Germany) are on the market. In addition, in China and Korea patient trials (hip surgery and hand fracture) are reported. This paper gives a brief outline of the current status of Mg-implants and which obstacles still have to be mastered. As an example for the special nature of Mg and its interaction with cells, a comparison is made between the influence of osteoblasts (bone forming cells) and fibroblasts (the most abundant cells in connective tissue) on the degradation layer underneath the cells.
DOI Link to Publication