Microbiologically Induced Corrosive Properties of the Titanium Surface

Abstract

Corrosion of titanium is the major concern when it is used for dental treatment. This study aimed to investigate the mechanism of the microbiologically induced corrosive properties of titanium. An experimental well was made of polymethyl methacrylate with pure titanium at the bottom. Viable or killed cells of Streptococcus mutans were packed into the well, and pH at the bacteria-titanium interface was monitored with and without glucose. Before and after 90-minute incubation, the electrochemical behavior on the titanium surface was measured by means of a potentiostat. The oxygen concentration under bacterial cells was monitored with oxygen-sensitive fluorescent film. The amount of titanium eluted was measured by inductively coupled plasma-mass spectrometry. The corrosion current and passive current under killed cells were low and stable during 90 min, while those under viable cells increased, regardless of the glucose-induced pH fall. The polarization resistance and oxygen concentration under killed cells were high and stable, while those under viable cells decreased. No elution of titanium was detected. Viable bacterial cells may form 'oxygen concentration cells' through metabolism-coupled oxygen consumption and subsequently induce corrosive properties of the titanium surface.

Titanium as a modifier of the peri‐implant microbiome structure

“…In addition, the oral microbiome has the potential to disrupt the biocompatible titanium dioxide surface layer . A specific example is Streptococcus mutans , which has been shown to increase the corrosion current and to induce titanium corrosion . We have shown that oral bacterial taxa are capable of affecting titanium electro‐conductive properties and can lead to spontaneous generation of electrical potential and accelerated titanium dissolution from titanium implants .…”

“…Streptococcus mutans, which has been shown to increase the corrosion current 49 and to induce titanium corrosion. 50 We have shown that oral bacterial taxa are capable of affecting titanium electro-conductive properties and can lead to spontaneous generation of electrical Shannon Diversity Streptococcus Relative Abundance iv.…”

Citric acid reduces oral biofilm and influences the electrochemical behavior of titanium: Anin situandin vitrostudy

“…Therefore, citric acid may act similarly, degrading the natural oxide film and interacting with the surface to form a TiH 2 layer that, posteriorly, is covered by a new spontaneously formed TiO 2 film. Additionally, because the oral biofilms can affect the electrochemical behavior of cpTi surface, discs only exposed to the treatments (without previous biofilm formation) were used in the electrochemical tests to check the direct influence of citric acid on titanium surface.…”

Evaluation of oral microbial corrosion on the surface degradation of dental implant materials

“…Streptococcus species, especially S. mutans , are opportunistic bacteria known to accelerate corrosion of Ti‐based dental implants . Bacterial adhesion is expected to induce corrosion of metallic substrates via metabolic byproducts including lactic acid and hydrogen peroxide which can lower the corrosion resistance of Ti .…”