Document Type
Dissertation
Date of Award
1982
Abstract
Three alloys used for surgical applications, 316L stainless steel (Fe-Cr-Ni, ASTMF138), Co-Cr-Mo (ASTM F75) and T1-6A1-4V (ASTM F136) were investigated to determine the elemental constituents released during corrosion and to determine the tissue responses elicited under in vitro and in vivo conditions. In vitro testing involved exposing cell cultures to varying concentrations of synthetic solutions based on the alloy’s chemical composition and independently to solutions of the elements comprising the alloy. In vivo testing involved implanting the alloys in rabbits and injecting synthetic solutions of corrosion products at the implant-to-capsule interface. In vitro exposure of cell cultures to synthetic stainless steel corrosion product solutions demonstrated toxic responses (inhibited growth rates and altered cellular morphologies) at concentrations as low as 3.0 ppm (representing in ppm 2.0 Fe, 0.6 Cr, and 0.42 Ni). Cell cultures exposed to Co-Cr-Mo solutions demonstrated toxic responses at 1.5 ppm (representing in ppm 1.0 Co, 0.45 Cr, and 0.09 Mo). Individually Fe, Ni, Co, or Mo demonstrated nontoxic responses at these low concentrations. However, chromium was the most toxic. Cells exposed to chromium solutions demonstrated abnormal morphologies above a concentration of 0.375 ppm. Cell cultures exposed to Ti-6A1-4V solutions demonstrated toxic effects at 6.25 ppm (representing in ppm 5.6 Ti, 0.378 A1, and 0.25 V). Individually none of these elements were toxic at these concentrations where collectively a toxic response was observed. Vanadium was the most toxic element of this alloy, demonstrating toxicity above 0.75 ppm.Histological examinations of fibrous tissue capsules by optical microscopy showed a relative difference between alloys but no direct correlations between tissue response and concentration of solutions injected at the interface. However, transmission electron microscopic analysis of the cellular capsules showed a direct correlation. With increasing concentration, representative cellular ultrastructures showed a decrease in rough endoplasmic reticulum, a more diffuse plasma membrane, an increase in cytoplasmic vaculozation, and a decrease in cellular organization. This trend was consistent for both the in vivo and in vitro cells. Thus, the overall tissue response was dependent on the types and quantities of ions released during biocorrosion.
Recommended Citation
Lucas, Linda Chambers, "Biocompatibility Investigations of Surgical Implant Alloys." (1982). All ETDs from UAB. 7154.
https://digitalcommons.library.uab.edu/etd-collection/7154
Comments
PhD - ProQuest publication number 8316253