Effect of surface treatment methods on the shear bond strength between resin cement and all-ceramic core materials

This study compared the influence of various surface treatments on the shear bond strength between resin cement and lithium disilicate glass-ceramics. A series of 120 lithium disilicate ceramic samples were prepared to compare the effect of different surface treatments on the shear strength of a luting cement bonded to two all-ceramic systems. IPS Empress 2 and IPS e.max Press ceramic samples were fabricated according to the manufacturer's instructions. The ceramic samples were divided into the following 6 surface treatment groups for each ceramic system: 1—no treatment (C), 2—airborne-particle abrasion (A), 3—acid etching (E), 4—airborne-particle abrasion + acid etching (AE), 5—Nd:YAG laser (L), 6—Nd:YAG laser + acid etching (LE). Resin cement was then bonded to the treated ceramic surfaces and light polymerized. The shear bond strengths of the specimens were measured using a universal testing machine. Two-way ANOVA and Tukey HSD (α = 0.05) test were used to determine differences in shear bond strength between the groups. The ANOVA revealed significant differences between the treatment groups and ceramic types (p < 0.05). The shear bond strengths of IPS Empress 2 were significantly higher than those of IPS e.max Press.

► We examine the influence of surface treatments on the ceramic cores.
► Surface treatments affect the bond strength between ceramic and resin cement.
► Etching is necessary to obtain a strong shear bond between resin and ceramic.
► Nano crystals may affect the shear bond strength of resin cement to ceramic cores.