title: Plastic strains during stent deployment have a critical influence on the rate of corrosion in absorbable magnesium stents.
abstract: Magnesium stents are a promising candidate in the emerging field of absorbable metallic stents (AMSs). In this study, the mechanical and corrosion performance of dog-bone specimens and a specific stent design of a magnesium alloy, WE43, are assessed experimentally in terms of their corrosion behaviour and mechanical integrity. It is shown that plastic strains that are induced in the struts of the stent during stent deployment have a critical influence in directing subsequent corrosion behaviour within the material. In addition, the deployment and scaffolding characteristics of the magnesium stent are elucidated and contrasted with those of a commercial stainless steel stent. The magnesium stent is found to support higher levels of cyclic strain amplitude than the stainless steel stent, even prior to degradation, and this may play a role in reducing in-stent restenosis. This study provides new insights into the experimental performance of a current AMS design and material whilst demonstrating the critical influence of plastic strain on the corrosion performance and scaffolding ability of an AMS.
authors: School of Mechanical and Manufacturing Engineering, Dublin City University, Dublin 9, Ireland. emmet.galvin3@mail.dcu.ie.
authors: Emmet
authors: http://orcid.org/0000-0002-4589-3514
authors: E
authors: Galvin
authors: Vasorum Ltd., 2012 Orchard Avenue, Citywest Campus, Dublin 24, Ireland.
authors: Christy
authors: C
authors: Cummins
authors: University of Yamanashi, 4-3-11 Takeda, Yamanashi, Kofu-City, Japan.
authors: Shoichiro
authors: S
authors: Yoshihara
authors: School of Mechanical and Manufacturing Engineering, Dublin City University, Dublin 9, Ireland.
authors: Bryan J
authors: BJ
authors: Mac Donald
authors: Department of Mechanical and Manufacturing Engineering, School of Engineering and Trinity Centre For Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, The University of Dublin, Dublin 2, Ireland.
authors: Caitríona
authors: C
authors: Lally
mesh_terms: D020341:Absorbable Implants; D000497:Alloys / Q000737:chemistry; D000818:Animals; D001807:Blood Vessel Prosthesis; D019245:Compressive Strength; D017076:Computer-Aided Design; D003343:Corrosion; D004285:Dogs; D055119:Elastic Modulus; D019544:Equipment Failure Analysis; D008274:Magnesium / Q000737:chemistry*; D011474:Prosthesis Design; D015607:Stents; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: D000497:Alloys; D008274:Magnesium
keywords: Absorbable metallic stents; Biodegradable magnesium alloys; Biomaterials; Cyclic strain; WE43