The role of oral microbiota in accelerating corrosion of Ti6Al4V: An electrochemical study

Abstract

This study examines the effect of oral microflora on the corrosion behavior of Ti6Al4V alloy in an aerobic environment. Electrochemical tests reveal that microbial activity significantly accelerates corrosion, increasing the corrosion current density from 4.8 nA/cm² under sterile conditions to 11.6 nA/cm². Fluorescence imaging confirms non-uniform biofilm formation, which creates localized microenvironments that promote pitting. Acid-producing bacteria, such as Streptococcus mutans, lower the pH of artificial saliva to approximately 6.5, enhancing metal dissolution. Scanning electron microscopy (SEM) further reveals pronounced pitting corrosion in microbial-inoculated samples. These findings underscore the need for advanced surface treatments and protective strategies to enhance the corrosion resistance of Ti6Al4V alloys in biomedical applications.