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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.

Purpose: To evaluate staining- and aging-dependent changes in the color and translucency of 3D-printed resin-modified ceramics (RMC). Methods: Specimens (n= 5 per condition and material) were fabricated from test materials: Permanent Crown Resin (PCR), Crowntec (CT), Vita Enamic (VE) and Tetric CAD (TC). Specimens were stained in wine, coffee, tea, and water (control) and exposed to artificial accelerated aging (AAA). Color measurements were obtained using a spectrophotometer at baseline (T0) and at 3.5 (Tl) and 7 (T2) days after immersion. For AAA, measurements were obtained at baseline (T0) and after exposure to controlled irradiance of 150 kJ/m² (T1) and 300 kJ/m² (T2). Mean and standard deviations were calculated on CIEDE2000 color differences (ΔE00), translucency parameter (TP00) and treatment-dependent changes in the translucency parameter (ΔTP00). Differences between materials and test conditions were tested by one-way ANOVA (a== 0.05). Results were additionally interpreted using visual color difference thresholds in dentistry ΔE00= 0.8 for the 50:50 perceptibility threshold (PT) and ΔE00= 1.8 for the 50:50 acceptability threshold CAT). ΔTP00 values were interpreted using 50:50 TPT00= 0.6 and 50:50% TAT00= 2.6. Results: Statistically significant differences were found among the materials when exposed to the different test conditions. At the T0-Tl time interval. the highest color difference was found with wine (0.1-2.2) on all materials except CT, which showed the highest ΔE00 with AAA (2.5). The second highest color differences were obtained upon exposure to AAA (0.2-2.5) and tea (0.5-1.1). The TP00 at baseline ranged from 5.1 to 9.8. Significant differences in ΔTP00 were found among the tested materials and staining/aging conditions, but no significant differences were found among the staining/aging intervals (T0-T1, T0-T2 and T1 -T2). [ABSTRACT FROM AUTHOR]

A measure of developmental instability (DI), body fluctuating asymmetry (FA), the Raven's Advanced Progressive Matrices (RAPM), and other cognitive tests on a group of 19 healthy male volunteers on whom cortical volume, white matter, overall brain volume, and cross-sectional areas of the corpus callosum and planum temporale were assessed. However, multiple regression analyses yields effects of FA on RAPM scores and a general intelligence principle component independent of cortical volume.

Undocumented immigrants often experience multiple chronic stressors that over time can increase health risk. This qualitative study used data from 7 focus groups and 15 key informant interviews to identify relevant protective factors to the heath of undocumented immigrants in the U.S. Findings showed that at the individual level, undocumented immigrants rely primarily on motivation to cope with adversity, while also relying on family support and community cohesion at the interpersonal level. At the policy level, safe neighborhoods and non-stigmatizing environments, protection from abuse/exploitation, and activism were identified as protective factors. English proficiency was also identified as important. [ABSTRACT FROM AUTHOR]

This article discusses a study that compared clinical in-office bleaching of 6% hydrogen peroxide (HP) with and without light, plus three nights of treatment with 16% carbamide peroxide (CP). Visual and instrumental color measurements were performed on 77 subjects immediately, one week, and two weeks after in-office bleaching. Data were analyzed at 0.05 level of significance using paired t-test and patient surveys. Results indicated shades were 6 to 7 shades lighter visually depending on light or no light treatment respectively, and 7.4 with respect to ΔE*. Some mild tooth or gingival sensitivity was reported. The study concluded that bleaching was significantly greater between light and no-light groups visually, but not instrumentally. [ABSTRACT FROM AUTHOR]

Developmental chronic low-level lead (Pb) exposure disrupts central nervous system function and diminishes neurocognition. Microglial cell activation might contribute to these deficits. The present study evaluated the effects of developmental sub-chronic low-level lead exposure on microglial cells and the possible effectiveness of a natural anti-inflammatory intervention with apigenin to mitigate these effects. From PND 0 to 28, 87 C57BL/6 J mice were exposed to one of six treatment conditions: 0 ppm Pb; 30 ppm Pb; 430 ppm Pb; 30 ppm Pb + 400 ppm apigenin; 430 ppm Pb + 400 ppm apigenin; or 400 ppm apigenin, via dams' drinking water. Following sacrifice, brain tissue was harvested and microglial cells were labeled via immunohistochemistry and counted within the dentate gyrus (DG) using unbiased stereology methods. It was hypothesized that developmental sub-chronic low-level lead exposure would increase microglial cell numbers within the DG and that apigenin treatment may mitigate these effects. A significant effect of treatment group was found and post-hoc analyses revealed that Pb-exposure generated an increased number of microglial cells as compared to controls. Interestingly, the 30 ppm Pb with apigenin treatment group did not generate microglial cell numbers different from the control group unexposed to Pb. These results suggested that developmental sub-chronic low-level lead exposure increased microglial cell activation within the DG and that, at low-levels of Pb exposure, apigenin treatment may mitigate these effects. These results provided the groundwork for studies that could identify an effective intervention to alleviate the effects of developmental chronic low-level lead exposure in child neurocognition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: To evaluate staining- and aging-dependent changes in the color and translucency of 3D-printed resin-modified ceramics (RMC)., Methods: Specimens (n= 5 per condition and material) were fabricated from test materials: Permanent Crown Resin (PCR), Crowntec (CT), Vita Enamic (VE) and Tetric CAD (TC). Specimens were stained in wine, coffee, tea, and water (control) and exposed to artificial accelerated aging (AAA). Color measurements were obtained using a spectrophotometer at baseline (T0) and at 3.5 (T1) and 7 (T2) days after immersion. For AAA, measurements were obtained at baseline (T0) and after exposure to controlled irradiance of 150 kJ/m² (T1) and 300 kJ/m² (T2). Mean and standard deviations were calculated on CIEDE2000 color differences (ΔE₀₀), translucency parameter (TP₀₀) and treatment-dependent changes in the translucency parameter (ΔTP₀ ₀). Differences between materials and test conditions were tested by one-way ANOVA (α= 0.05). Results were additionally interpreted using visual color difference thresholds in dentistry ΔE₀₀= 0.8 for the 50:50 perceptibility threshold (PT) and ΔE₀₀= 1.8 for the 50:50 acceptability threshold (AT). ΔTP₀₀ values were interpreted using 5058;50 TPT₀₀= 0.6 and 50:0% TAT₀₀= 2.6., Results: Statistically significant differences were found among the materials when exposed to the different test conditions. At the T0-T1 time interval, the highest color difference was found with wine (0.1-2.2) on all materials except CT, which showed the highest ΔE₀₀ with AAA (2.5). The second highest color differences were obtained upon exposure to AAA (0.2-2.5) and tea (0.5-1.1). The TP₀₀ at baseline ranged from 5.1 to 9.8. Significant differences in ΔTP₀₀ were found among the tested materials and staining/aging conditions, but no significant differences were found among the staining/aging intervals (T0-T1, T0-T2 and T1-T2)., Clinical Significance: Staining- and artificial aging-dependent changes of 3D-printed and milled resin modified ceramics used for definitive restorations could represent a challenge in terms of restoration acceptability or dissatisfaction. Staining and aging conditions produced significant color changes, while translucency changes were not significant., Competing Interests: The authors do not have any financial interest in the companies whose materials are included in this article. The milled Resin-Modified Ceramic materials were donated by VITA Zahnfabrik and Ivoclar Vivadent., (Copyright©American Journal of Dentistry.)