Effect of Thermal Aging on Shear Bond Strength of Self Adhesive Resin Cements to Different CAD/CAM Ceramics

Abstract

INTRODUCTION: The aim of this study was to evaluate the effect of short term thermal aging process on shear bond strength of self-adhesive resin cements to feldspathic and lithium disilicate CAD/CAM ceramics. METHODS: 80 ceramic specimens of 1.5 mm thickness were obtained from the Vita Mark II (VIT) and IPS e.max CAD (MAX) blocks and IPS e.max CAD discs were sintered. All specimens were etched with 5% hydrofluoric acid and silane was applied to the ceramic surfaces. Ceramic specimens were divided into two groups and Panavia SA (PSA) and RelyX U200 (RXU) self adhesive resin cements were applied to the ceramic surface with 3 mm diameter and 2 mm high plastic tubes. After cementation specimens were divided into two sub-groups, and half of the specimens were subjected to thermal aging at 5,000 rpm between 5-55°C in the bath for 30 sec (n=10). After thermal aging, all specimens were shear tested at a speed of 0.5 mm/sec with a Universal tester. The data were evaluated by one way ANOVA test (SPSS 23). RESULTS: The highest shear bond strength value among the groups was measured in VIT-PSA ceramics without thermal aging (10,50 +- 2,67 MPa), while the lowest values were measured in MAX-RXU samples with thermal aging (6,81 +- 1,37 MPa) (p<0.01). Although the thermal aging process applied at 5,000 cycles in the same groups resulted in a decrease in the bond strength values, it was not statistically significant (p>0.01). DISCUSSION AND CONCLUSION: The thermal aging process did not cause a significant decrease in the bond strength of self adhesive resin cements to feldpathic and lithium disilicate CAD/CAM ceramics in the short term.

Keywords

• feldpathic and lithium disilicate cad/cam ceramics
• self adhesive resin cement
• shear bond strength