Background and surrounding colors affect the color blending of a single-shade composite

Abstract This study evaluated the background and effect of surrounding colors on the color blending of a single-shade composite used in a thin layer. Disc-shaped specimens (1.0 mm thickness) were built with the Vittra APS Unique composite surrounded (dual specimens) or not surrounded (simple specimens) by a control composite (shade A1, A2, or A3). Simple specimens were also built with only control composites. The specimen color was measured against white and black backgrounds with a spectrophotometer (CIELAB system). The whiteness index for dentistry (WID) was calculated for simple specimens. Differences (ΔE00) in color and translucency parameters (ΔTP00) between the simple/dual specimens and the controls were calculated. The translucency adjustment potential (TAP) and color adjustment potential (CAP) were estimated based on the ratios between data from simple and dual specimens. The Vittra APS Unique composite showed higher WID values than the controls. No differences between ΔTP00_SIMPLE and ΔTP00_DUAL were observed for any of the shades. The composite shade did not affect TAP values. The lowest values of ΔE00_SIMPLE and ΔE00_DUAL were observed for shade A1 regardless of the background color. For the white background, ΔE00_SIMPLE values did not differ from those of ΔE00_DUAL for all shades. Only A1 showed ΔE00_DUAL values lower than ΔE00_SIMPLE when the black background was used. The highest modulus of CAP (negative values for the white background) was observed when shade A1 surrounded the Vittra APS Unique composite. The color blending ability of the single-shade resin composite used in a thin layer was affected by both the surrounding shade and background color.摘要 本研究评估了环绕色与背景色对薄层单色调复合树脂色彩混融性能的影响。本研究制备了厚度为1.0mm的圆盘状试样：将Vittra APS Unique复合树脂采用对照复合树脂（色调为A1、A2或A3）环绕（对偶试样）或不环绕（简单试样）的方式制备，同时制备仅使用对照复合树脂的简单试样。采用搭载CIELAB色彩系统的分光光度计，在白色与黑色背景下测定试样的色彩参数，并针对简单试样计算牙科用白度指数（WID, whiteness index for dentistry）。计算简单/对偶试样与对照组间的色彩差值（ΔE00）与半透明参数差值（ΔTP00），并基于简单试样与对偶试样的检测数据比值，估算半透明调节潜能（TAP, translucency adjustment potential）与色彩调节潜能（CAP, color adjustment potential）。 结果显示，Vittra APS Unique复合树脂的WID值高于对照组复合树脂；所有色调的ΔTP00_SIMPLE与ΔTP00_DUAL均无显著差异；复合树脂色调对TAP值无显著影响。无论背景色为何，A1色调的ΔE00_SIMPLE与ΔE00_DUAL值均为最低；在白色背景下，所有色调的ΔE00_SIMPLE与ΔE00_DUAL值均无显著差异；仅当采用黑色背景时，A1色调的ΔE00_DUAL值低于ΔE00_SIMPLE值。当A1色调环绕Vittra APS Unique复合树脂时，CAP的绝对值最高（白色背景下CAP值为负值）。本研究表明，薄层单色调树脂复合材料的色彩混融性能同时受环绕色调与背景色的影响。