Cement Adhesion to High-strength Ceramics Using Priming-agent: Effect of Sandblasting

Objective: This study assessed the influence of alumina-blasting surface conditioning on the shear bond strength of a dual-cured resin luting agent to high-strength ceramics, with the cementation process performed using an MDP-based ceramic primer. Methods: 40 square-shaped (10 × 10 × 10 mm) ceramic specimens were obtained and divided into two groups: 20 zirconium-oxide (In-Ceram YZ, VITA Zahnfabrik) (YZ) and 20 alumina (In-Ceram AL, VITA Zahnfabrik (AL) ceramic blocks. For each group, half of the specimens (n=10) were submitted to two different surface treatments: airborne-particle abrasion with 110 µm aluminium-oxide particles (Sand_110); the others ten were left untreated (Control). In order to fabricate composite specimens, and to limit the luting area, metal rings with an internal diameter of 4mm and a height of 2mm were filled with resin composite. For all ceramic surfaces a ceramic primer (Clearfil® Ceramic Primer, Kuraray) containing a phosphate functional monomer (MDP) was applied; ceramic blocks and composite specimens were bonded together using a dual-cured resin luting cement (Clearfil® Esthetic Cement, Kuraray) according to manufacturer's instructions. The cemented samples were light-cured and stored in distilled water at 37°C for 7 days. Shear bond strength (SBS) was evaluated using a universal testing machine. Values were calculated in MPa; the data were analyzed by one way ANOVA (p < 0,05). Results: For YZ group the mean shear bond strengths were: Control 19.44 ± 5.11; Sand_110 18.68 ± 4.19; (p = 0,719). For AL group the mean shear bond strengths were: Control 16.14 ± 4.56; Sand_110 23.31 ± 9.35; (p = 0,043). Conclusions: For alumina specimens, a positive combined effect of sandblasting and ceramic primer application produced highest shear bond strength values; on zirconia specimens tested, the application of primer without sandblasting performs a reliable cement adhesion.