Resin cements effect on the final color of novel monolithic CAD/CAM restorations

This study investigated the effect of resin cement shade on the final color of computer aided design/computer aided manufacture (CAD/CAM) restorations.

Thirty CAD/CAM block specimens were fabricated (14×12×1.5 mm) by cutting blocks (Vita Mark II [VM], Vita Enamic [VE], and Lava Ultimate [LU]). Forty cement specimens were prepared (14×12×0.2 mm) using resin cement (RelyX Ultimate Tr, A1, A3O, Bl). Color measurements of CAD/CAM specimens were made without (control) and with each /shade of resin cement (test) with a spectrophotometer. Color differences (ΔE00) between the control and test groups were calculated and analyzed by 2-way ANOVA and subsequent pairwise testing. Comparisons were performed by using Tukey's multiple comparison tests (α=0.05).

Both cement shade and interaction between cement shade CAD/CAM block type parameters were significant on color differences (P<0.05). A3O cement resulted in a clinically unacceptable color differences (ΔE00>2.25) for each tested CAD/CAM blocks. ΔE00 values of VM_A1 and VE_A1 groups were also higher than clinically unacceptable level (ΔE00>2.25). ΔE00 value of VE_Tr was lower than visually perceptible level (∆E00≤1.30). There was no statistically significant difference found between the ∆E00 values of CAD/CAM blocks in the same shade of cement groups (P>0.05).

Tested CAD/CAM blocks were similarly affected by the cement shade and thus may have similar optical features.