Corrosion Behaviour and Biocompatibility of 316 Stainless Steel as Biomaterial in Physiological Environment

Abstract

Although stainless steel is a material widely used for biomedical applications, its surface properties for long term application are still a serious concern. 316L stainless steel (SS 316L) is a material commonly used in dentistry for orthodontic braces, wires and in some cases as dental crowns. The pH value of natural saliva from the oral cavity can undergo sudden modification due to food products which are rich in citric acid. The electrochemical corrosion behavior of 316L stainless steel was evaluated in two simulated body fluid solutions, Fusayama-Mayer artificial saliva with pH=5 and Fusayama-Mayer artificial saliva adjusted with citric acid to a pH=1.58 which simulates the environmental conditions of the oral cavity. The surface of SS316L was investigated by optical microscope before and after corrosion assays. The electrochemical corrosion behavior was studied by open circuit potential, potenitodynamic polarization and linear polarization. Optical microscopy was used to characterize the corrosion damage after the electrochemical assays.