Effect of Cavity Dimensions on Color Adjustment of Single-Shade versus Multi-Shade Resin Composite Restorations: An In Vitro Study

Abstract

Aim: To assess the effect of different cavity dimensions on the color adjustment potential of single-shade resin composite with or without blocker versus multi-shade resin composite. Materials and methods: 120 class V cavities were prepared with the following dimensions: Group 1 (G1): mesio-distally = 3 mm, occluso-gingivally = 2 mm, depth = 1.5 mm, Group 2 (G2): mesio-distally = 3 mm, occluso-gingivally = 1.5 mm, depth = 2 mm, Group 3 (G3): mesio-distally = 3 mm, occluso-gingivally = 2 mm, depth = 2 mm, Group 4 (G4): mesio-distally = 3 mm, occluso-gingivally = 2 mm, and depth = 2.5 mm. Color assessment was done using VITA Easyshade® V. Three restorative materials were used: PALFIQUE OMNICHROMA BLOCKER (Tokuyama Dental Corporation, Japan) [B], PALFIQUE OMNICHROMA (Tokuyama Dental Corporation, Japan) [O], 3M™ Filtek™ Z350 XT Universal Restorative (3M ESPE Dental Products, USA) [Z]. The total color difference between the teeth and restorations was expressed by ΔE. All restorations were subjected to 10,000 thermal cycles. One way ANOVA, Bonferroni post hoc, paired t test, and Multiple ways ANOVA tests were used to analyze the results statistically. Results: G4 recorded the highest mean value, followed by G3, then G1, with the lowest mean value in G2. Regarding subgroups: subgroup “B” recorded the highest value, followed by subgroup “O”, then subgroup “Z”, with a significant difference between the subgroups (p=0.00). Regarding thermocycling, a significantly higher mean value was recorded after thermocycling. Conclusions: Increasing the cavity size and depth decreases the color adjustment of the restorative material.