This study was designed to evaluate the effect of different surface treatment methods on the shear bond strength between resin cement and four Zirconia ceramics.
Methods:
A total of 160 zirconia ceramic samples were prepared with Y-TZP zirconia ceramics (Cercon®, In-Ceram® YZ, IPS e.max® ZirCAD and Lava™). The zirconia specimens were divided into four groups (n = 10) according to surface treatments as follows: Control (No treatment), HF acid etching for 90s, Neodymium:yttrium–aluminium–garnet (Nd:YAG) laser was applied with 300-µm fiber probe at 3W, 20Hz, 150 mJ with 100µs pulse duration after the graphite powder on the ceramic surface and CoJet™ Sand sandblasting with silica powder at a pressure of 3.0 bar, distance of 10 mm for 20 seconds. Resin cement was then bonded to the treated ceramic surfaces using a composite-filling instrument and then light polymerized for 20 s. The specimens were subjected to thermocycling for 2000 cycles between 5 and 55 0C before test. The shear bond strengths of the specimens were measured using a universal testing machine at a crosshead speed of 0,5 mm /min. Two-way ANOVA and Tukey HSD tests were performed to evaluate the data (α = 0.05).
Results:
The ANOVA revealed significant differences between the treatment groups and ceramics (p<0.05). Nd:YAG laser irradiation increased the shear bond strength values in In-Ceram® YZ and Lava™ groups. Lava™ group showed significantly higher bond strength values than the other groups (p<0.05).
Conclusions:
Shear bond strength of resin cement to zirconia ceramics were affected by Nd:YAG laser irradiation. The bond strength values were not influenced by acid etching effectively.