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Biodegradable Stents: Biomechanical Modeling Challenges and Opportunities

  • James E. MooreJr.
  • Joao S. Soares
  • Kumbakonam R. Rajagopal
Article

Abstract

Biodegradable implants show great potential in many areas of medicine, and have already demonstrated success in simple applications such as sutures. For more complex devices, such as vascular stents, there are considerable challenges associated with the use of biodegradable materials. These materials typically are weaker than the metals currently used to construct stents, so it is difficult to ensure sufficient strength to prop open the artery and alleviate symptoms acutely. It is even more challenging to design a stent that provides structural support for a predictable, appropriate time to facilitate artery healing. These challenges are evident when one considers that there are no biodegradable stents on the US market despite more than 20 years of development efforts. This review summarizes previous efforts at implementing biodegradable stents, discusses the specific challenges involved, and presents a recently developed biodegradable material modeling framework that can benefit this exciting field.

Keywords

Polymer Corrodible metals Scission Degradation Erosion Mechanical properties 

Notes

Acknowledgments

The authors gratefully acknowledge support from the National Institutes of Health (R01 EB000115 to JEM), the Portuguese Fundação para a Ciência e Tecnologia (SFRH/BD/17060/2004 and SFRH/BPD/63119/2009 to JSS), and the National Science Foundation (to KRR).

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© Biomedical Engineering Society 2010

Authors and Affiliations

  • James E. MooreJr.
    • 1
  • Joao S. Soares
    • 2
    • 3
  • Kumbakonam R. Rajagopal
    • 4
  1. 1.Department of Biomedical EngineeringTexas A&M UniversityCollege StationUSA
  2. 2.Department of MathematicsCenter for Mathematics and its Applications (CEMAT), Instituto Superior TécnicoLisbonPortugal
  3. 3.Department of MathematicsModeling and Scientific Computing (MOX), Politecnico di MilanoMilanoItaly
  4. 4.Department of Mechanical EngineeringTexas A&M UniversityCollege StationUSA

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