Page 32 - Magnesium-based supports for stem cell therapy of vascular disease - Mónica Echeverry Rendón

CHAPTER 2
corrosion and biological properties of surface-modified Mg, still is an excellent and pivotal way to bridge between physicochemical studies and preclinical evaluation. The challenge is to find a model closer between in vivo and in vitro tests, so it could be easier to predict the future behavior of a material or based-Mg formulation previous to the implant [16,42,120–122].
Another important consideration about based-magnesium implants is to reach a proper solution ensuring the right balance between degradation of the material and formation of a new tissue and keeping the adequate elimination of the material. Other characteristics such morphology and interface interactions need to be improved.
8. Conclusions
Stents for the treatment of cardiovascular diseases are usually made of non-degradable metallic materials such as Ni-Ti alloy or Cr-Co alloy. Their permanent implantation, however, increases the risk for long-term restenosis. Biode- gradable materials are a novel option to solve this problem. Magnesium is a promising yet challenging material and although has been used as biodegradable implant in different applications such as orthopedic and cardiovascular research. Magnesium is promising due its mechanical properties and good absorption in the body without causing adverse side effects, while it is a natural constituent of the body and essential for physiology. The disadvantage of Mg is its high reactivity and fast dissolution in physiologic fluids. However, this can be controlled for different techniques as incorporation of alloying elements or with the surface modification of the material by coatings. In this context, base Mg-alloys have been used more frequently and new formulations including elements to improve mechanical and biological properties are currently more employed. However, the answer about why not using commercial pure magnesium is still not resolved. This work collects some information around magnesium and its alloys offering an overview about what points can be studied in detail in order to made contributions around this topic.
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