Microtensile Bond Strength Between Zirconia Core and Veneering Porcelain After Different Surface Treatments

The long-term clinical success of all-ceramic restorations requires sufficient bond strength between the veneering ceramic and substructure. The present study compared the effects of three methods of surface treatment on the microtensile bond strength of the veneering porcelain to zirconia. Twelve zirconia blocks were randomly divided into four groups of aluminum oxide (Al O ) air abrasion, carbon dioxide (CO ) laser irradiation, erbium-doped yttrium aluminum garnet (Er:YAG) laser irradiation, and control samples (no surface treatment). After surface treatment, the zirconia blocks were veneered with porcelain. To assess the surface topographies, four surface-treated specimens were left uncoated. Microtensile bond strength was tested in each group and was statistically analyzed by one-way ANOVA and post-hoc Tukey's test. Surface topographies were examined by using scanning electron microscopy (SEM). The highest and lowest microtensile bond strength values were recorded in the Al O (43.6±10.0 MPa) and control groups (34.7±8.2 MPa, P