Characterization of dental metal–ceramic interfaces immersed in artificial saliva after substructural mechanical metallization with titanium

The purpose of this study was to analyze the mechanical strength and microstructure of dental metal–ceramic interfaces immersed in acidic artificial saliva after mechanical metallization of a NiCr-based substrate. Commercial NiCrMo alloy and dental porcelain were characterized before the production of metal–ceramic specimens. Therefore, a group of metallic surfaces was mechanically metallized with Ti. After that, metal–ceramic interfaces were produced and immersed in an electrochemical cell containing artificial saliva. In order to accelerate the corrosion of the interfaces, a potential of 0.75 V was applied on the metallic substrate for 30 min. 3-point bending tests of the metal–ceramic systems were carried out according to the ISO-9693 standard before and after immersion tests. The metallic surfaces as well as the metal–ceramic interfaces were analyzed by SEM–EDS. There was a decrease of the mechanical strength of conventional metal–ceramic interface after immersion. However, the mechanical strength of the samples with metallized interfaces remained unaltered after immersion in artificial saliva.