Comparison of different silane primer systems on composite resin bond strength to lithium disilicate ceramics

This study aims to evaluate the effect of different primers applied to HF acid-etched lithium disilicate ceramics on the shear bond strength between ceramic specimens and composite resin after thermal aging. 72 disc specimens with a thickness of 1.5 mm were prepared from three different types of lithium disilicate ceramics: IPS e.max CAD, CEREC Tessera, and GC Initial LiSi Block. The specimens were divided into six groups, with 12 samples in each group. The surfaces were treated with 9.5% HF acid. In Gluma group, Gluma Ceramic Primer and Gluma Bond Universal were applied in sequence. For Compo-B group, a mixture of Ceramica Silane Activator and Nova Compo-B Plus universal adhesive was applied, followed by Nova Compo-B Plus. After composite application, all specimens underwent 5000 thermal cycles. A universal testing machine was used to perform the shear bond strength test. Two-way ANOVA and Tukey HSD tests were conducted to compare MPa values according to the surface treatments. Statistically significant differences were found in shear bond strength values among the different repair systems applied to lithium disilicate ceramics (p < 0.001). The GC Initial ceramic group showed significantly higher bond strength compared to the other groups. The use of different primers significantly affected the shear bond strength of lithium disilicate glass ceramics. The immediate application of silane resulted in higher bond strength values in lithium disilicate ceramics.