Comparative study of the chemical resistance of titanium nitride and stainless steel in media of the oral cavity

We have shown that TiN powders practically do not react with biochemical media in the body. Using the polarization curve method, x-ray phase analysis, and Auger-electron spectroscopy of the electrode surface, we have studied the reaction of titanium nitride and 12Kh18N10T stainless steel with distilled water, a 3% solution of NaCl, HCl, and gastric juice. We have demonstrated the high corrosion resistance of both materials in H2O (which is also typical for saliva): but in the presence of salt and when gastric juice is ejected from the esophagus into the oral cavity, the corrosion resistance of steel may decrease by several orders of magnitude compared with TiN. In the case of a titanium nitride electrode, we have also established the mechanism of the protective (inhibiting) action of organic reagents contained in the biochemical media, while stainless steel dissolves in gastric juice significantly more rapidly than in hydrochloric acid with the same pH 2.0.