Microshear bond strength of resin cement to a zirconia‑reinforced lithium silicate glass ceramic using different surface treatments

The purpose of this study was to evaluate the effect of different surface treatments on the microshear bond strength (µSBS) of resin cement to zirconia‑reinforced lithium silicate ceramic and to compare it with lithium disilicate ceramic.

In this in vitro study, 80 specimens containing two glass ceramics of IPS e.max press and VITA SUPRINITY were prepared and categorized into four groups according to the surface treatments (n = 10) as Group 1 (C): no treatment (control); Group 2 (HF): etching with 9% hydrofluoric acid (HF) for 90 s followed by silane application; Group 3 (SPH): sandblasting with Al2 O3 particles (50 μm), etching with 35% phosphoric acid for 40 s followed by application of silane and adhesive (Clearfil liner bond F); and Group 4 (SB): sandblasting with Al2 O3 followed by silanization. Then, a resin cement (Panavia F2) was applied to the prepared ceramic surfaces. All samples were subjected to thermal aging (5000 cycles, 5–55). The µSBS test was evaluated and failure modes were recorded. Data were analyzed using the Shapiro–Wilk, two‑way analysis of variance and Tukey’s Honest Significant Difference post hoc tests (P < 0.05).

IPS e.max press samples revealed significantly higher µSBS values compared to VITA SUPRINITY (P < 0.001), in whole surface treatments. The HF group showed the highest µSBS value, followed by the SPH and SB groups, respectively (P < 0.001). Adhesive failure was recorded as a predominant failure mode.

The adhesion performance of IPS e.max press was significantly higher than VITA SUPRINITY. The common surface treatment protocol including HF application followed by silanization was the most effective surface treatment for both glass ceramics.