Shade-Matching Capacity of Omnichroma in Anterior Restorations

Objective: To evaluate if there is evidence of shade matching and color change over a month, with OMNICHROMA (Tokuyama) composite restorations, after bleaching with Opalescence™ Boost™ (Ultradent). Methods: Ten extracted teeth with varying shades A1-D4 were randomly chosen, n=10. Samples were restored with an OMNICHROMA shade matching composite. Class V preparations (approximately 6mm x 2 mm x 1.5 mm) were acid etched with Ultra-Etch ® (Ultradent, 40% Phosphoric Acid) for 30 seconds, rinsed and air dried. Teeth were bonded with Tokuyama Universal Bond® (8th-generation bonding agent), filled and finished/polished with Super Snap and OneGloss (Shofu). The teeth were stored in distilled water at 37̊C for 24 hours. Shades were evaluated by 2 blinded calibrated clinicians using the VITA Classic shade guide and given an overall matching score between the restoration and the tooth, using a scale of matches, somewhat matches, and does not match. Additionally, on the Crystaleye Spectrophotometer (Olympus) shade evaluations were recorded at a total of 5 locations, 4 sites around the restoration, and the 5th site directly over the restoration. Samples were completely covered in bleach with Opalescence Boost (Ultradent, 40% Hydrogen Peroxide) for 20 minutes according to manufacturer's instructions, two consecutive times, rinsed and placed in distilled water for 24 hours. L*a*b*, ∆E and Vita shades were recorded at 24 hours, 1 week, 2 weeks, 4 weeks post bleaching using the Crystaleye Spectrophotometer (Olympus). Each sample was evaluated under the Olympus stereomicroscope (SZX16). L*a*b* values of the 4 sites around the restoration were averaged and compared to the L*a*b* values of the restoration. Stata 15 was used, and significant level was set at 0.01. Results: Average color change after bleaching was 3 shades. Shade matching scores by the clinicians showed the composite matched 100%, for all teeth at all time intervals. There was no significant difference in the L*a*b* values between the restoration and tooth at each time interval. Conclusion: The shade of the filling matched that of the adjacent enamel pre- and post-bleaching.