Bond strength of resin cements to leucite-reinforced ceramics

Objective: The aim of this study was to evaluate the shear bond strength (SBS) of two resin cements to four leucite-reinforced ceramics. Material and methods: Forty ceramic blocks (4 mm wide, 14 mm length and 2 mm thick) were used and the samples abraded with aluminum oxide (90 µm). The samples were divided into eight groups (n = 5). Two resin cements (conventional RelyX ARC and self-adhesive RelyX U100 - 3M ESPE) were bonded to Creapress (CRE-Creation/Klema), Finesse All-Ceramic (FIN-Dentsply/ Ceramco), IPS Empress Esthetic (IEE-Ivoclar Vivadent) and Vita PM9 (PM9-Vita). For all groups and in each ceramic block, after application of 10% hydrofluoric acid and silanation, three Tygon tubings were positioned over the ceramics, which were filled in with the resin cements (light-cure for 40 s). The tubings were removed to expose the specimens in format of cylinders (area: 0.38 mm2) and samples were stored in relative humidity at 24±2 °C for one week. After this period, each sample was attached to testing machine and the specimens were submitted to shear bond test (applied at the base of the specimen/cement cylinder with a thin wire/0.2 mm) at speed of 0.5 mm/ min, until failure. The results were analyzed by two-way ANOVA (resin cements and ceramic systems) and Tukey test (p