Physical Properties of a One-Shade Composite After Wine Short-Term Immersion

Objectives: One-shade composites are claimed to esthetically simulate all shades with one single nominal shade to chameleon the surrounding tooth structures. We hypothesized that the physical properties, color (DE), sorption (SP) and solubility (SL) of one-shade composites is affected by immersion in red wine. We investigated these physical properties for a one-shade composite (Omnichroma (OM), Tokuyama Dental America) and compared with respective properties of conventional multi-shade (Tetric EvoCeram (TE) and bleach-shade (Tetric EvoCeram Bleach XL (TBL), Ivoclar-Vivadent) composites after short-term immersion in red wine.
Methods: Composite discs (15mm x 1.5mm) were prepared using custom molds. A single increment of composites was placed to overfill molds, which were covered with a glass slip. Specimens were photopolymerized for 20s (10s/side) using a LED-unit (VALO, Ultradent; irradiance >1.1W/cm²). All physical properties (DE, SP, SL) were measured using the same specimen (n=5/composite) at baseline (after preparation at dry condition) and after a short-term immersion (1x/day for 30min) in red wine (RW). Control specimens were immersed in reverse osmosis water. Samples were maintained in PBS between immersion cycles. Procedure was repeated for 7 days. Color coordinates were measured according to the CIELAB color scale using a colorimeter (Spectro2go, BYK) against a black and white background. SP and SL were determined according to the ISO-4049. Changes in color were considered significant at ΔE>2. Data were analyzed by repeated-measures ANOVA and post-hoc Bonferroni tests (α=0.05).
Results: Difference in ΔE after immersion in wine was higher than 2 only for TBL, for both assessments made against black and white backgrounds. Likewise, SP and SL after immersion in wine was shown to be significantly higher for composite TBL (p<0.05), but not for OM and TE.
Conclusions: Short-term immersion in red wine did not affect tested physical properties of OM. Future analyses will assess potential changes in OM translucency parameter and mechanical stability.