Abstract
Purpose: The purpose of this study was to evaluate the long-term durability of the bonds between self-adhesive luting agents and yttria-stabilized partially stabilized zirconia (Y-PSZ) and the effect of phosphoric acid etching as a surface pre-treatment to Y-PSZ.
Materials and Methods: A total of 180 Y-PSZ disks were divided into two groups; the control group and the phosphoric acid etching group prior to the bonding with one of three self-adhesive luting agents; Panavia SA Cement Plus Automix (SAP), RelyX Unicem2 Automix (UC2), or Maxcem Elite Chroma (MXE). Bonded specimens were stored in distilled water, for 1 day, 30 days, or 150 days. After storage, the tensile bond strength was measured using a universal testing machine. The data were statistically analyzed using Welch's -test and Welch's -test with Bonferroni correction ( = 0.05).
Results: The tensile bond strength of each luting agent measured more than 15 MPa after 1 day of immersion in distilled water with or without phosphoric acid etching. There were no significant differences between SAP and UC2 after 30 days and 150 days ( > 0.05) of immersion. SAP and UC2 showed significantly higher bond strength than MXE after 30 days and 150 days < 0.05) of immersion. There were no significant differences between with/without phosphoric acid etching in all groups ( > 0.05).
Conclusion: Durability of self-adhesive luting agent to Y-PSZ was material-dependent. A surface pre-treatment with phosphoric acid etching to Y-PSZ did not affect the bond strength of self-adhesive luting agent to Y-PSZ.
