The Effects of Biodegradation on the Cytocompatibility of Bioresorbable Fe-Based Scaffolds: A Review

This work aims to review current trends in research within the field of iron-based scaffolds for orthopaedic applications. Current research is trapped in a ‘see-saw’ type problem where an increase in corrosion rate of the base metal is required to accelerate the degradation process making the resorption time compatible with the healing time. This is done via several methods including porosity control, cathodic element addition and/or patterning and alloying. In turn, this increase in corrosion rate causes the local concentration of metallic ions to increase beyond the toxicity limit for osteoblast type cells, thus negatively effecting cytocompatibility. This is most pronounced when considering the orthopaedic environment, in which static conditions provide for increased local ion concentrations, resulting in local toxicity. However, research from the medical field of Thalassemia may help solve this dilemma by providing chelation medicine for patients undergoing implantation of resorbable orthopaedic scaffolds, throughout the resorption period. Excretion of iron would then be provided mainly through bowel movement and urination.