Different Zirconia Surface Treatments: Strategies to Enhance Adhesion in Zirconia-Based Dental Restorations

All-ceramics have been widely used in dentistry. The favorable mechanical properties and high biocompatibility of zirconia ceramics lead to using it as an alternative to the conventional porcelain-fused-to-metal (PFM) restorations. However, its major limitation is the difficulty of achieving proper bonding due to the chemical inertness of its surface. The current work aims to show the application of the zirconia in dental fields and to discuss the various surface treatment options available. Hydrofluoric acid treatment of the zirconia surface did not result in durable bonding. A combination of mechanical and chemical preparation is essential to reach an activated surface. Different mechanical preparation methods were used as airborne-particle abrasion, tribo-chemical silica coating, low-fusion porcelain layers application, selective infiltration etching, laser irradiation, plasma spraying and zirconia ceramic powder coating. Chemical preparation involves the use of silane and primers. However, the proper universal bonding technique of zirconia has yet to be established, owing to insufficient supporting evidence in literature. This review highlights the use of zirconia ceramics in dental field and its proper bonding protocol achieved via different surface treatments.