The Effect of Different Types of Surface Treatment on the Strength of the Bond Between Veneering Ceramic and Titanium

Prosthetic restorations made of titanium and its alloys are often veneered with ceramics. While Co-Cr or Ni-Cr alloys are subjected to high-temperature oxidation before ceramic application, this is not possible for titanium due to its high reactivity; hence, the resulting layers are thick, porous, and have poor adhesion. An alternative method for obtaining an oxide layer is anodic oxidation, or anodization. This paper presents the shear strength of the titanium–ceramic bond after different anodization variants. The following reagents were used for oxidation: Group A—1 molar phosphoric acid (V), Group B—1 molar sulfuric acid (VI), Group C—1 molar mixture of the above acids, and Group D—2% Na2SiO3 at pH = 13.1. The veneering ceramic was applied to the treated sample surfaces, and the samples were subjected to a shear test. Anodic oxidation was found to increase the joint stress compared to a control group of unanodized samples (Group 0). The highest strength was achieved for samples from groups A and B. Hence, anodic oxidation improved the titanium–ceramic adhesion of polished samples compared to the control group.