The shear bond strength between resin luting systems and zirconia

Abstract

Objective To evaluate the shear bond strength (SBS) between resin cement and zirconia under different experimental conditions. Methods In present study, six cubic zirconia specimens with a side length of 2 cm were cut by computer aided design/computer aided manufacturing (CAD/CAM) equipment and sintered afterwards. According to different experimental conditions, eight kinds of dual-curing resin cements were divided into 13 groups, such as: (1) Monobond N + Multilink N (MMN) ; (2) Ivoclean + Monobond N + Multilink (IMM) ; (3) Ivoclean + Monobond N + Multilink N [no sandblasting, IMM (ns) ]; (4) Tetric N-Bond Universal + Multilink Speed (TUM) ; (5) Multilink Speed (MLS) ; (6) Z-Prime Plus + TheraCem (ZPT) ; (7) Z-Prime Plus + Duo-Link (ZPD) ; (8) Single Bond Universal + RelyX U200 (SRU) ; (9) RelyX U200 (RXU) ; (10) Single Bond Universal + RelyX Ultimate Clicker (SRU) ; (11) OptiBond Versa + Kerr NX3 (OVK) ; (12) Clearfil Universal Bond + Clearfil SAC (CUS) ; (13) Clearfil SAC (SAC) . Each resin cement was injected into a transparent mould after self-mixing, and put onto the zirconia surface without pressure when finally being light-cured (n = 20) . The SBS test of the all specimens was performed after 24 hours of 37 ℃ water storage, and the results were statistically analyzed by One-Way ANOVA, SPSS 19.0 software (P<0.05) . The fracture mode on zirconia surface was observed by electron stereoscopic microscope. Results The bond strength (MPa) of resin cements in a descending order was: OVK (27.51 ± 3.65) >IMM (27.28 ± 3.79) >SRC (26.77 ± 3.62) > CUS (25.36 ± 3.10) >TUM (25.22 ± 4.88) >ZPD (23.96 ± 6.25) >MLS (23.13 ± 2.74) > MMN (23.07 ± 3.71) >SAC (22.20 ± 3.59) >IMM (ns) (21.99 ± 3.50) >SRU (19.19 ± 2.27) >ZPT (18.62 ± 2.08) >U200 (15.04 ± 4.02) . Conclusions (1) The SBS of resin cements was material-dependent. (2) The SBS of resin cement could be improved by sandblasting, using a special cleaning agent or universal adhesive as a primer on zirconia surface. Key words: Zirconium, oxides; Resin cements; Adhesives; Shear strength; Surface treatment