Does Gender Influence Color Matching Quality?

Objectives: To compare shade matching skills of color normal males and females

Esthetic color training in dentistry

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Color adjustment potential of resin composites

The purpose of this study was to evaluate color adjustment potential (CAP) of resin composites. Two shades of each of eight commercial resin composites and one control shade were evaluated. Visual (color competent observers, controlled conditions) and instrumental color evaluations (spectroradiometer, spectrophotometer) were performed. The data were analyzed by analysis of variance, Fisher's PLSD intervals for comparison of means, and Spearman's rank order correlation. Instrumental color adjustment potential (CAP-I) ranged from - 0.51 to 0.74, and corresponding Fisher's PLSD intervals were 0.1 and 0.05, respectively (p lt 0.0001, power 1.0). Visual color adjustment potential (CAP-V) ranged from 0.10 to 0.78, and corresponding Fisher's PLSD intervals were 0.2 and 0.1, respectively (p lt 0.0001, power 1.0). The greatest overall color shifting between test shades in isolation and the same shades surrounded by control shade were recorded for HRi ENA enamel, followed by Clearfil Majesty ES2. The highest visual CAP (blending) was recorded for Herculite Ultra, HRi ENA enamel, and Clearfil Majesty ES2. Within the limitation of the study, it was found that color adjustment potential (CAP) was composite and shade-dependent. Positive CAP was recorded both instrumentally and visually for majority of composites and shades. Overall, the measured color difference reduction associated with positive CAP was 31%, while the average visual CAP was 43%. Resin composites with pronounced color adjustment potential interact with surrounding dental restorations. Introduced CAP-V and CAP-I were indirect measurements of blending (optical illusion)

Whitening-dependent changes of fluorescence of extracted human teeth

Objective: To evaluate in vitro the fluorescence properties of extracted human teeth whitened with 40% hydrogen peroxide. Materials and Methods: A total of 28 extracted human teeth were pumiced for 1 minute using a low-speed dental handpiece and a disposable rubber cup. Pre-whitening fluorescence measurements (T0), maximum excitation (Ex(max)), maximum emission (Em(max)), and maximum intensity (I(max)10(8)), were performed using a spectrofluorometer. After T0 measurements, the teeth were whitened using the in-office method with 40% hydrogen peroxide, three times for 20 minutes. The fluorescence parameters were measured under the same conditions 7 and 14 days after bleaching (T1 and T2, respectively). Results: Ex(max) exhibited a broader range 7 days after whitening and decreased after 14 days. The Em(max) and I(max)10(8) displayed a narrower range after whitening. The mean Ex(max) differed significantly between the time points (F = 20.09. P LT .001). The corresponding analysis for the mean Em(max) differed significantly between the time points (F=16.69, P LT .001). The same was true for the mean I(max)10(8) (F = 9.69, P LT .001). Conclusions: Within the limitations of this study, whitening provoked statistically significant changes in fluorescence of the intact teeth in vitro

Colorimetric (CIEDE2000) comparison between two shade guides used for visual evaluation of tooth whitening efficacy

Introduction/Objective The objective of this study was to perform colorimetric comparison between two shade guides used for visual tooth whitening monitoring. Methods VITA Bleachedguide 3D-Master (BG) and value scale of VITA classical A1–D4 (VC) were evaluated (n = 3) using a non-contact spectroradiometer. Ranges, distribution, and correlation among color parameters were evaluated using CIEDE2000 color difference formula. In addition, optimized whiteness index for dentistry (WID), and Yellowness Index E313 (YI) were analyzed. ANOVA and Fisher’s PLSD test at a 0.05 level of significance were used in statistical analysis. Results The lightness (L’), chroma (C’), and hue (h’) ranges for BG were 20.4, 25.9, and 19.1, respectively. The corresponding ranges for VC were 15.3, 10.9, and 20.6. R2 values for individual color coordinate/tab arrangement were higher for BG than VC. The same is true for R2 values of pairs of color coordinates for BG/VC: L’C’ = 0.89/0.33, L’h’ = 0.88/0.53, and C’h’ = 0.70/0.51. BG also exhibited better agreement between the manufacturer’s tab arrangement with ΔE’, WID and YI. The ΔE’ between the lightest and the darkest BG and VC tab were 20.6 and 13.2, respectively. The average ΔE’ among the adjacent tabs were 1.9 (0.5) for BG (corresponding to two shade guide units, SGU) and 3.0 (1.0) for VC (1 SGU). Conclusion VITA Bleachedguide 3D-Master exhibited wider L’, C’, ΔE’, WID, and YI ranges compared to value scale of VITA classical A1–D4 shade guide and better distribution of evaluated color parameters. This, along with the presence of several shades lighter than B1 of VC, recommends the use of BG for visual evaluation of tooth whitening efficacy

Staining and aging-dependent changes in color of CAD-CAM materials

Consumption of some beverages and aging may affect the color of dental materials used in fixed prosthodontics, but their effect on recently introduced materials is not well known

Color compatibility between dental structures and three different types of ceramic systems.

To assess color compatibility between dental structures (human enamel and dentine) and three different types of ceramic systems. Samples (1 and 2 mm-thick) of extracted tooth (containing dentine and enamel areas) and three ceramic systems with different shades and opacities (HT-High Translucent, T-Translucent) were prepared for this study: Vita Suprinity-VS (HT, T; A1, A2, A3, A3.5, B2, C2, D2) (Vita Zahnfabrik); Vita Enamic-VE (HT, T; 1M1, 1M2, 2M2, 3M2) (Vita Zahnfabrik) and Noritake Super Porcelain EX-3-NKT (A1, A2, A3, A3.5, B2, C2, D2) (Kuraray Noritake Dental). Reflectance measurements of all samples were performed over black backgrounds using a non-contact spectroradiometer (SpectraScan PR-670, Photo Research) under a CIE 45°/0° geometry. CIE L*a*b* color parameters were measured and CIELAB/CIEDE2000 color differences (ΔE00/ΔE*ab) and corresponding Coverage Error (CE) of ceramic system for dentine or enamel samples were calculated. Color data was analyzed using one-way ANOVA and post-hoc multiple comparisons tests. CE values were interpreted by comparisons with available 50:50% acceptability color threshold (AT) for dentistry. Statistically significant differences in lightness were found among all ceramic systems and human dentine (p  0.05) with VEHT. Thin samples (1 mm) of dentine and enamel showed significant statistical differences (p  Color coordinates of evaluated esthetic ceramic systems were statistically different from those of human dentine in almost all cases. The evaluated ZrO2 lithium silicate glass-ceramic (VS), with its two levels of translucency, provided lower CE values with human enamel samples while conventional feldspathic ceramic (NKT) and hybrid ceramic systems (VE) demonstrated a better color compatibility with dentin samples