Bond Strength of Resin Cement to Yttrium-Stabilized Tetragonal Zirconia Ceramic Treated with Air Abrasion, Silica Coating, and Laser Irradiation

Abstract

The purpose of this study was to evaluate the shear bond strength of a resin cement to yttrium-stabilized tetragonal zirconia (Y-TZP) surfaces treated with air abrasion, silica coating, or CO(2), Er:YAG, or Nd:YAG laser irradiation, or irradiated by each laser after air abrasion. Optimized methods are needed to improve the adhesive bonding between resin cement and Y-TZP ceramic. Twelve specimens were irradiated with each laser at different parameters and examined by scanning electron microscopy to determine which parameters to use in this study. One hundred forty-one Y-TZP discs were assigned to nine groups: C, no treatment; AA, air abrasion; CJ, silica coating; ER, Er:YAG laser; ND, Nd:YAG laser; CO, CO(2) laser; AA+ER, air abrasion + Er:YAG laser; AA+ND, air abrasion + Nd:YAG laser; AA+CO, air abrasion + CO(2) laser. The composite cylinders were fabricated. After the surface treatments, the specimens were silanized and composite cylinders were cemented with the resin cement. The shear bond strength test was performed after specimens were stored in water for 24 h and after thermocycling for 500 cycles. The highest bond strength was obtained in the AA group and was similar to that of the CJ group. In C, ER, CO, ND, AA+ND, and AA+CO groups, the shear bond strengths were similar to each other according to the Duncan test results. The lowest bond value was obtained in the AA+ER group. Although air abrasion and silica coating were the most effective surface treatment methods, CO(2) and Er:YAG laser irradiation alone or Nd:YAG laser irradiation after air abrasion may be used as an alternative treatment method to increase the bond strength between resin cement and Y-TZP material.