Exploring the Role of Zirconia Surface Treatments on the Properties and the Material’s Bonding to Resin Cement

Objectives: 1. To evaluate the bond strength of yttria-tetragonal zirconia polycrystalline (Y-TZP), lithium-disilicate, and feldspathic ceramics to 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing and non-MDP resin cements. 2. To evaluate the effect of ultrashort-pulse laser (UPL) on surface treatment on Y-TZP surface properties, the material’s bond strength to resin cement, and the effect of thermal stress on bond strength. Methods: Lithium-disilicate (LD), feldspathic porcelain (FP), and Y-TZP blocks received surface treatment according to the manufacturer recommendations (LD and FP: hydrofluoric acid, Y-TZP: alumina-blasting), and were luted to human dentin using MDP-containing (UL) or non-MDP adhesive system (UN). Specimens were microtensile tested. Fully-sintered Y-TZP received either no treatment (CTL) or one treatment of: ALB, SIL, or UPL. UPL consisted of either dots (LSD) or lines (LSL) patterns. Surface roughness, contact angle, and crystalline phases were evaluated. Y-TZP were cemented to composite using resin-based cement combined with a silane and MDP-containing adhesive. Specimens were incubated for 48 hours, then microtensile tested directly or after thermocycling. Results: The type of ceramic and the resin cement both had significant effects on bond strength (P≤.001). Y-TZP showed significantly lower bond strength (pPh.D