Materials science

Bending

Ceramic

Nuclear physics

Ultimate tensile strength

Surface roughness

Universal testing machine

Physics

Irradiation

Lithium disilicate

Stereo microscope

Composite material

Dental porcelain

Flexural strength

Journal of Prosthodontics

To evaluate the effect of different surface treatments on mechanical and optical properties of lithium disilicate ceramic (IPS e.max CAD), 2 resin nanoceramics (Lava Ultimate, GC Cerasmart), and polymer-infiltrated ceramic network material (Vita Enamic).CAD/CAM blocks were sectioned into 4 × 1 × 14 mm3 bars for three-point bending test and 1 × 8 × 8 mm3 square specimens were obtained for color and translucency measurements. Bar-shaped and square specimens were divided into five groups according to the surface treatment method as: control (no treatment), hydrofluoric acid etching, airborne-particle abrasion, 2 W and 3 W Er,Cr:YSGG laser irradiation (n = 10). Three-point bending test was carried out on a universal test machine with a 1 mm/min crosshead speed. Color and translucency measurements were performed with a spectrophotometer and repeated after surface treatments. Flexural strength, translucency parameter, and ΔE values were calculated and data were statistically analyzed using one-way ANOVA and Bonferroni post hoc tests. ΔE values >1.2 and >2.7 were considered as perceptible and unacceptable, respectively.All surface treatment methods decreased the flexural strength of all tested materials (P < 0.05) except for 2 W laser-irradiated and airborne-particle abraded Vita Enamic and 2 W laser irradiated Lava Ultimate (P > 0.05). Color changes of lithium disilicate specimens were not perceptible except for airborne-particle abraded specimens. All ΔE values of resin-based materials were above the perceptibility threshold. Acid-etched and 3 W laser-irradiated GC Vita Enamic specimens revealed unacceptable color changes. The translucencies of resin-based materials significantly decreased after all surface treatment applications.Surface treatments affected the flexural strength and optical properties of CAD/CAM restorative materials. Er,Cr:YSGG laser irradiation with 2 W energy level may be an alternative surface treatment method for CAD/CAM materials.

The Effect of Surface Treatments on the Mechanical and Optical Behaviors of CAD/CAM Restorative Materials