In Vitro Evaluation of Physical and Mechanical Properties of Light-Curing Resin Cement: A Comparative Study.

Abstract

Objective The aim of study was to evaluate in vitro the surface hardness, sorption, solubility, and color stability of three light-cured resin cements, namely RelyX Veneer (RLX), Variolink Veneer (VLK), and All Cem Veneer (ACV). Materials and Methods Cylindrical samples (15 × 1 mm) were made for each group using a metallic mold ( n = 10). Vickers microhardness test was performed, and average hardness was calculated from three indentations (300 gf/15s) per sample. The sorption and solubility of the materials were evaluated according to ISO 4049:2009 based on three samples weighing: initial ( m 1 ), after immersion in distilled water for 7 days ( m 2 ), and final (after removal of all moisture [ m 3 ]). The color change was observed using a digital spectrophotometer, at three different time points, baseline, 1 day, and 1 week of immersion in coffee and distilled water (control). Statistical Analysis Shapiro–Wilk test was used to analyze the normality of the data, and groups were compared using Kruskal–Wallis and Mann–Whitney tests. A significance level of 5% was used. Results RLX showed the highest microhardness mean values (36.96 VHN), but higher sorption (23.2 µg/mm 3 ) and solubility (2.40 µg/mm 3 ), with statistically significant differences with the other groups. For color stability, higher ∆E was observed for the samples immersed in coffee ( p = 0.009). The VLK resin cement presented statistically significant differences from the other groups, with higher color changes in coffee at 1 day (15.14) and after 1 week (23.65). Conclusion RLX resin cement showed better hardness results. All materials tested performed satisfactorily for sorption and solubility according to ISO 4049:2009. All materials showed high-staining values after 1 week of immersion in coffee.