Staining Analysis of Resin Cements and Their Effects on Colour and Translucency Changes in Lithium Disilicate Veneers

This study evaluated the colour and translucency changes in resin cements and lithium disilicate veneer restorations, as well as the sorption and solubility of cements after staining. Four resin cements (G-CEM ONE, RelyX Universal, Panavia V5, Variolink Esthetic) were tested. Cylindrical specimens and LiSi veneer restorations cemented to a G-aenial Universal Injectable dentine base (N = 10/group) were stained in black tea for 72 h. Changes in colour (∆E) and the translucency parameter (∆TP) were analyzed using a spectrophotometer, while sorption and solubility were calculated via mass/volume formulae. G-Cem and RelyX exhibited significantly lower ∆E than Variolink and Panavia (p < 0.001), while RelyX uniquely showed increased ∆TP (p < 0.001). The ∆E of cemented veneers ranged from 2.7 ± 0.5 (G-Cem) to 3.9 ± 0.7 (Panavia), with decreased translucency after staining across groups (p > 0.05). The initial TP positively correlated with the ∆E of both cements and veneer restorations, while the ∆E of cements correlated with that of veneer restorations. RelyX had the highest sorption, and Variolink showed the highest solubility, though neither correlated with colour changes. Resin cements influenced colour changes in veneer restorations post-staining, with colour differences associated with initial cement translucency but independent of sorption and solubility.