J Korean Dent Sci.  2015 Dec;8(2):82-88. 10.5856/JKDS.2015.8.2.82.

Effects of Light-Curing on the Immediate and Delayed Micro-Shear Bond Strength between Yttria-Tetragonal Zirconia Polycrystal Ceramics and Universal Adhesive

• Lee Y
• Woo JS
• Eo SH
• Seo DG

• KMID: 2154082
• DOI: http://doi.org/10.5856/JKDS.2015.8.2.82

Abstract

PURPOSE
To evaluate the effect of light-curing on the immediate and delayed micro-shear bond strength (microSBS) between yttria-tetragonal zirconia polycrystal (Y-TZP) ceramics and RelyX Ultimate when using Single Bond Universal (SBU).
MATERIALS AND METHODS
Y-TZP ceramic specimens were ground with #600-grit SiC paper. SBU was applied and RelyX Ultimate was mixed and placed on the Y-TZP surface. The specimens were divided into three groups depending on whether light curing was done after adhesive (SBU) and resin cement application: uncured after adhesive and uncured after resin cement application (UU); uncured after adhesive, but light cured after resin cement (UC); and light cured after adhesive and light cured resin cement (CC). The three groups were further divided depending on the timing of microSBS testing: immediate at 24 hours (UUI, UCI, CCI) and delayed at 4 weeks (UUD, UCD, CCD). microSBS was statistically analyzed using one-way ANOVA and Student-Newman-Keuls multiple comparison test (P<0.05). The surface of the fractured Y-TZP specimens was analyzed under a scanning electron microscope (SEM). RESULT: At 24 hours, microSBS of UUI group (8.60+/-2.06 MPa) was significantly lower than UCI group (25.71+/-4.48 MPa) and CCI group (29.54+/-3.62 MPa) (P<0.05). There was not any significant difference between UCI and CCI group (P>0.05). At 4 weeks, microSBS of UUD group (24.43+/-2.88 MPa) had significantly increased over time compared to UUI group (P<0.05). The SEM results showed mixed failure in UCI and CCI group, while UUI group showed adhesive failure.
CONCLUSION
Light-curing of universal adhesive before or after application of RelyX Ultimate resin cement significantly improved the immediate microSBS of resin cement to air-abrasion treated Y-TZP surface. After 4 weeks, the delayed microSBS of the non-light curing group significantly improved to the level of light-cured groups.

Keyword

Delayed micro-shear bond strength; Immediate micro-shear bond strength; Light-curing; Resin cements; Universal adhesive; Yttria-stabilized tetragonal zirconia polycrystals ceramic

MeSH Terms

Adhesives*
Ceramics*
Resin Cements
Adhesives
Ceramics
Resin Cements