Objective: The purpose of this study was to evaluate the effect of different surface treatments on bond strength between In-Ceram Zirconia ceramic and Panavia Fluoro Cement. Background Data: Although several surface treatments have been used on In-Ceram Zirconia, no study has been conducted to investigate the effect of the Nd:YAG laser. Materials and Methods: Nine In-Ceram Zirconia blocks (10 × 10 × 6 mm) received three different surface treatments (n = 3 per group): group 1—Al ₂ O ₃ sandblasting + silane; group 2—Al ₂ O ₃ sandblasting + Rocatec Plus + silane; and group 3—Al ₂ O ₃ sandblasting + Nd:YAG laser + silane. Resin cement was applied and light-cured, followed by the application of composite resin. The blocks were sectioned to obtain square rods with a cross-sectional dimension of 1.0 mm ² (n = 12 per group). Microtensile bond strength ( μ TBS) was recorded using a universal testing machine at a cross-head speed of 0.5 mm/min and expressed in megapascals (MPa). Results: All groups yielded statistically significantly different μ TBS mean values: group 1 (11.81 ± 3.12 MPa); group 2 (15.75 ± 4.45 MPa); group 3 (18.70 ± 5.14 MPa) (ANOVA and Tukey's test; α = 0.05). Conclusion: Nd:YAG laser irradiation is an effective surface treatment for bonding between In-Ceram Zirconia and Panavia Fluoro Cement.

SUMMARY: The aim was to evaluate, in vitro, the influence of different computer-aided design/computer-aided manufacturing (CAD/CAM) materials (IPS e.max CAD, Vita Enamic, and Lava Ultimate) and thicknesses (0.6 mm and 1.5 mm) on the fracture resistance of occlusal veneers. Sixty human third molars were prepared to simulate advanced erosion of the occlusal surface, and the teeth were randomly divided into six experimental groups (n=10) according to the material and thickness used to build the veneers. Ten sound teeth formed the control group. The veneers were adhesively luted and submitted to mechanical cyclic loading (1 million cycles at 200-N load). The fracture resistance test was performed in a universal testing machine. The failures were classified as “reparable” and “irreparable.” According to two-way analysis of variance and the Tukey test, the interaction (material × thickness) was significant (p=0.013). The highest fracture resistance was obtained for IPS e.max CAD at a 1.5-mm thickness (4995 N) and was significantly higher compared to the other experimental groups (p0.05). The experimental groups did not differ significantly from the sound teeth (3991 N) (p>0.05). The failures were predominantly repairable. The occlusal veneers of IPS e.max CAD, Vita Enamic, and Lava Ultimate, with thicknesses of 0.6 mm and 1.5 mm, obtained fracture resistances similar to those associated with sound teeth.

Objective: The aim of this study was to evaluate the effect of different surface treatments on bond strength between In-Ceram Alumina (VITA) and Panavia Fluoro Cement (Kuraray), and to verify the association between bond strength values and the percentage of remaining cement on the ceramic surface. Background Data: Although several conventional surface treatments have been used on aluminous ceramic, no study investigated the effect of the Nd:YAG laser. Methods: Nine In-Ceram Alumina blocks (10 × 10 × 6 mm) received three surface treatments: group 1, Al ₂ O ₃ sandblasting + silane; group 2, Al ₂ O ₃ sandblasting + Rocatec Plus + silane; and group 3, Al ₂ O ₃ sandblasting + Nd:YAG Laser + silane. Resin cement was applied and light cured, followed by the application of composite. Blocks were sectioned to obtain sticks with a cross-sectional area of 1.0 mm ² . Microtensile bond strength (µTBS) was recorded in a universal testing machine at a crosshead speed of 0.5 mm/min. Scanning electron microscopy images of the fractured areas were used to calculate the amount of remaining cement on the ceramic substrate. Results: All treatments yielded statistically different µTBS values (MPa): group 1, 14.38 ^A ; group 2, 20.09 ^B ; and group 3, 23.21 ^C (ANOVAand Tukey's test,α = 0.05). Pearson's correlation coefficient for µTBS × percentage of remaining cement was r = 0.92 ( p < 0.05). Conclusions: The Nd:YAG laser was the most effective surface treatment, followed by Rocatec and Al ₂ O ₃ sandblasting. A strong positive association was found between bond strength values and percentage of remaining cement.