Color-Matching and Blending-Effect of Universal Shade Bulk-Fill-Resin-Composite in Resin-Composite-Models and Natural Teeth

Abstract

Objectives. To assess visually color-matching and blending-effect (BE) of a universal shade bulk-fill-resin-composite placed in resin-composite-models with different shades and cavity sizes and in natural teeth (extracted and patients' teeth). Materials and Methods. Resin-composite-discs (10 mm × 1 mm) were prepared of universal shade composite and resin-composite of shades: A1, A2, A3, A3.5, and A4. Spectrophotometric-color-measurement was performed to calculate color-difference (ΔE) between the universal shade and shaded-resin-composites discs and determine their translucency-parameter (TP). Visual assessment was performed by seven normal-color-vision-observers to determine the color-matching between the universal shade and each shade, under Illuminant D65. Color-matching visual scoring (VS) values were expressed numerically (1–5): 1: mismatch/totally unacceptable, 2: Poor-Match/hardly acceptable, 3: Good-Match/acceptable, 4: Close-Match/small-difference, and 5: Exact-Match/no-color-difference. Occlusal cavities of different sizes were prepared in teeth-like resin-composite-models with shades A1, A2, A3, A3.5, and A4. The cavities were filled by the universal shade composite. The same scale was used to score color-matching between the fillings and composite-models. BE was calculated as difference in mean-visual-scores in models and that of discs. Extracted teeth with two different class I-cavity sizes as well as ten patients' lower posterior molars with occlusal caries were prepared, filled by universal shade composite, and assessed similarly. Results. In models, the universal shade composite showed close matching in the different cavity sizes and surrounding shades (4 ≤ VS < 5) (BE = 0.6–2.9 in small cavities and 0.5–2.8 in large cavities). In extracted teeth, there was good-to-close color-matching (VS = 3.7–4.4 in small cavities, BE = 2.5–3.2) (VS = 3–3.5, BE = 1.8–2.3 in large cavities). In patients' molars, the universal shade composite showed good-matching (VS = 3–3.3, BE = −0.9–2.1). Conclusions. Color-matching of universal shade resin-composite was satisfactory rather than perfect in patients' teeth.

Analysis of the color matching of universal resin composites in anterior restorations

“…These new universal composites have, according to the manufacturers, the concept of a universal translucency and opacity that could match the tooth color in different clinical situations. There are few reports about the color differences of these composites in posterior restorations, 11,33,34 but there were still no data evaluating these composites for anterior restorations. The Vita shade of a resin composite is determined by the color properties of hue and chroma, while the translucency is straight related to the lightness (value) of the material 35 .…”

Evaluation of structural coloration of experimental flowable resin composites

“…29 Previous reports have shown that the blending effect was material and shade dependent and increased with the decrease in the restoration size and increase in translucency. 30 The acceptable threshold ranges from 2.0 to 4.0, and one-third of the studies in the literature have shown that 50% of observers accept a color difference at a threshold value of 3.7. 31 In one study, the CIELAB 50%:50% perceptual threshold in dentistry was ΔE*ab = 1.2, whereas the 50%:50% acceptance threshold was ΔE*ab = 2.7; more than half of the studies used a perceptual thresh- Though the EXs used the same spherical filler with an average particle size of 260 nm, E70 exhibited an acceptable match for the A4 artificial tooth at any cavity depth.…”

“…When two colors are displayed side by side, the blend, or perceived color of the area, shifts to the surrounding colors in the environment 29 . Previous reports have shown that the blending effect was material and shade dependent and increased with the decrease in the restoration size and increase in translucency 30 …”

Color match using instrumental and visual methods for single, group, and multi‐shade composite resins

“…This meant that OM blended in with the surrounding tooth structure, resulting in a reduced color difference between the two 6 . Abdelraouf et al 7 assessed the color match and BE of a universal shade composite (X‐TraFil) placed in composite resin models of different shades (Grandio; A1, A2, A3, A3.5, and A4) and cavity sizes, and in natural teeth. Spectrophotometric analysis was carried out to calculate the color difference ( ∆E ) between the universal shade and the other shades and visual scoring (VS) was done by seven observers.…”