Effect of different surface treatments on the shear bond strength between lithium disilicate glass-ceramic and resin cement

Abstract

Objective: The study aimed to evaluate the shear bond strength (SBS) of lithium disilicate glass-ceramic and resin cement using different surface treatments. Methods: Lithium disilicate blocks (Vintage LD Press ®) were prepared, etched with 4.5 % hydrofluoric acid, and randomly divided into seven groups (n=10), depending on the surface treatments: 1) no surface treatment (control), 2) Silane Primer (KS), 3) Signum® Ceramic Bond I (SGI), 4) Signum® Ceramic Bond II (SGI/SGII), 5) experimental silane (EXP), 6) experimental-silane/Signum® Ceramic Bond II (EXP/SGII), and 7) Experimental/Adper™ Scotchbond Multi-purpose Adhesive (EXP/ADP). The specimens were cemented to resin composite blocks with resin cement and stored in water at 37°C for 24 hours. The specimens underwent 5,000 thermal cycles and were subjected to the SBS test. Data were analyzed with Welch ANOVA and Games-Howell post-hoc tests (α=0.05). Mode of failure was evaluated under the Stereo Microscope. Results: The highest mean SBS showed in group EXP/ADP (45.49±3.37 MPa), however this was not significantly different from group EXP/SGII (41.38±2.17 MPa) (p≥0.05). The lowest SBS was shown in the control group (18.36±0.69 MPa). This was not significantly different from group KS (20.17±1.10 MPa) (p≥0.05). Conclusion: The different surface treatments significantly affected the SBS value between lithium disilicate and resin cement. The application of pure silane coupling agent with or without the application of an adhesive improved the shear bond strength value and bond quality.