“Effect of Two Adhesive Resin Cements with Two Polymerization Modes and Curing Intensities on the Color Stability and Shear Bond Strength to the Lithium Disilicate Material”

Abstract

Background: One of the greatest challenges in dentistry is the recreation of natural enamel and dentin optical properties. The all ceramic restorations gained great popularity during the last years, as they offer better esthetics and more conservation of the sound tooth structure. By selecting the proper ceramic material, a restoration with more natural appearance mimicking the natural teeth could be obtained. By the improvement in ceramic technology, fabrication of a thinner restorations with increased translucency can be obtained with a thickness ranging from 0.3 – 0.7 mm. Objectives: This study was designed to evaluate the effect of different polymerization modes of resin cement and curing intensities on color stability and Shear bond strength to lithium disilicate material. Materials and Methods: A total of 56 specimens were used in this study and were divided into two parts (color stability and shear bond strength). Each part was then divided into two groups according to the cement used (polymerization mode). The groups were subdivided into two subgroups according to the light curing device used (curing intensities) n=7. Color samples (part I) were constructed by injecting two resin cements (Panavia V5 amd Bisco choice 2) in a Teflon mold. The cements were then cured by two different light cure devices (Elipar Deepcure-L and BlueLEX LD-105). Results: Regarding shear bond strength testing, the cement type had a statistically significant effect on mean shear bond strength values, regardless of the curing device used indicating that light curing device had no statistically significant effect on mean shear bond strength values. Regarding the color change, cement type as well as curing device had a statistically significant difference on mean ΔE. Conclusion: Light cure resin cement showed better bond strength than amine free dual cure resin cement regardless the curing intensity. Amine free dual cure resin cement showed statistically significantly higher color shift than the light cure resin cement system.