Microshear bond strength of dual-cure resin cement in zirconia after different cleaning techniques: an in vitro study

PURPOSEThis study aimed to compare the microshear bond strength (µSBS) of dual-cure resin cement in CAD-CAM zirconia after different cleaning techniques.MATERIALS AND METHODSFifty discs of zirconia-based ceramic from Ivoclar Vivadent were embedded in acrylic resin. The discs were divided into five groups according to the cleaning methods used: Group 1: drying with spraying + sandblasting with Al₂O₃; Group 2: washed with water and dried with spraying + sandblasting with Al₂O₃; Group 3: washed with distilled water and dried with spraying + sandblasting with Al₂O₃ + zirconium oxide (Ivoclean); Group 4: washed with distilled water and dried with spraying + sandblasting with Al₂O₃ + potassium hydroxide (Zirclean); and Group 5: washed with distilled water and dried with spraying + sandblasting with Al₂O₃ + 1% NaClO. All of the groups were contaminated with artificial saliva for 1 minute and then cleaned. Statistical analyses were performed using ANOVA and Tukey''s tests. RESULTSThere were statistically significant differences among all groups for µSBS (P < .05). The group treated with zirconium oxide (Group 3) showed the highest µSBS (18.75 ± 0.23 MPa).CONCLUSIONWhen applied to zirconia, the cleaning methods affected the bonding with resin cement differently.