کاربرد منیزیوم در ایمپلنت های ارتوپدی

Table of Contents

 Introduction
Mechanical Deterioration
 In Vivo Degradation of Magnesium Alloys
 In Vivo Evaluation of Magnesium Alloys With Surface Treatments
 In Vitro Evaluation of Magnesium Alloys With Surface Treatments
 Effect of Manufacturing Processing on Degradation Rate
 Summary
 Remind and Learn
 Think and Challenge
References

Introduction

Magnesium alloys have been found suitable for orthopedic implants. However, the main challenge of this material is its degradation rate in vivo. The corrosion of magnesium alloy is due to the electrochemical reaction between the material and body’s ionized fluid. Therefore, its degradation is inevitable and recently the extensive attempts were taken to reduce the degradation rate while preserving the biocompatibility and cytocompatibility of the material for use in orthopedic and dental implants. Using magnesium alloys in trauma plates and screws is particularly promising due to their close mechanical properties with human cortical bone (40 GPa compared to 16 GPa) compared to stainless steel and titanium alloys. Likewise, fixation of bone fractures with biodegradable magnesium alloys would eliminate a secondary operation for implant removal. In general, the degradation of magnesium alloy would result in reduction of implant strength and accumulation of hydrogen gas, which prevents the tissue growth as a physical barrier. Various elements have been alloyed or coated to slow the degradation rate of the magnesium alloy. In this article, the challenges of magnesium alloys for use in trauma plating systems are reviewed. a