Glass Ceramic Spray-Coating Manipulation Improve the Adhesion of Yttria Tetragonal Zirconia Polycrystals Restoration to Dental Cement

Objectives: Yttria tetragonal zirconia polycrystals (Y-TZP) is an excellent dental restorative material with good biocompatibility and appearance, but the poor bonding properties of Y-TZP to other dental materials become a critical problem in clinical application.
Methods: A novel surface treatment method called "glass-ceramic spray deposition" was applied on Y-TZP. After spraying and sintering, a glass-ceramic coating (GCC) would form on the Y-TZP surface. The effect of GCC on the physicochemical properties changing of Y-TZP was evaluated using microscopy analysis. Shear bond strength testing was subjected to confirm the bonding properties of Y-TZP to cement.
Results: Glass-ceramics or zirconium-based ceramics have been widely used in various dental restorations; however, combining these two ceramic systems is rare. The current experiment successfully merged them, producing a dense GCC, and this coating was able to infiltrate the Y-TZP surface, resulting in high surface roughness and hydrophilic nature, thereby enhancing the bonding strength of the Y-TZP/resin system.
Conclusions: This research constitutes a novel and easy-to-operate surface modification technology. A glass-ceramic layer can be easily coated on Y-TZP by simple spraying and sintering in dental clinics; further, improving the adhesion performance of the Y-TZP/resin system. We believe that this finding makes a significant contribution to the literature.