Biomaterials

Biography

Biography: Regine Willumeit-Römer

Abstract

Aging populations and a rise in osteoporosis-related fractures will sustain a need for orthopaedic intervention. In addition, juvenile patients and active adults exhibiting risky sporting activities also require perfect care. So far, these indications are treated mainly with non-degradable metal implants or in some cases also polymers. From the patient’s point of view, degradable implants would clearly be preferred. Here degradable magnesium-based implants could become an alternative to permanent metallic implants which have to be removed after healing, or to replace degradable polymers which do not always show the required mechanical properties. 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. Therefore, the development of new biodegradable Mg-based implants is strongly relying on the understanding of the degradation process in the living organism and the creation of an appropriate test system in vitro. Still, the endeavor 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 in the market. In addition, in China and Korea patient trials (hip surgery and hand fracture) are reported.