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Introduction: In this study, the effects of adding titanium dioxide nanotubes (TiO2) to 3D‐printed denture base resin on the mechanical and physical properties of denture bases were examined for the first time. Methods: The specimens were digitally created using 3D builder software from Microsoft Corporation through computer‐aided design. In accordance with the test specifications for transverse strength, impact strength, hardness, surface roughness, and color stability, specimens were designed and printed with certain dimensions following relevant standards. TiO2 nanotubes (diameter: 15–30 nm and length: 2–3 μm) were added to the 3D‐printed denture base resin (DentaBase, Asiga, Australia) at 1.0% and 1.5% by weight. Flexural strength, impact strength (Charpy impact), hardness, surface roughness, and color stability were evaluated, and the collected data were analyzed with ANOVA followed by Tukey's post hoc test (α = 0.05). Field emission scanning electron microscopy (FESEM) and energy dispersive x‐ray spectroscopy (EDX) mapping were used to evaluate the dispersion of the nanotubes. Results: Compared with those of the control group (0.0 wt.% TiO2 nanotubes), the average flexural, impact, and hardness values of the 1.0 and 1.5 wt.% TiO2 nanotube reinforcement groups increased significantly. Both nanocomposite groups showed significant color changes compared to that of the pure resin, and there was a considerable reduction in the surface roughness of the nanocomposites compared to that of the control group. Conclusion: Adding TiO2 nanotubes to 3D‐printed denture base materials at 1.0 and 1.5 wt.% could enhance the mechanical and physical properties of the material, leading to better clinical performance. Clinical Significance: In terms of clinical applications, 3D‐printed denture base material has been shown to be a viable substitute for traditional heat‐cured materials. By combining this with nanotechnology, existing dentures could be significantly enhanced, promoting extended service life and patient satisfaction while addressing the shortcomings of the current standard materials. [ABSTRACT FROM AUTHOR]

The longevity and acceptance of aesthetic dental materials are directly proportional to color stability. The aim of this study was to analyze the relationship between the use of multivitamins and the color stability of dental restorative materials. A total of 45 discs of nanohybrid composite, 45 of Reinforced Glass Ionomer (RGI), and 45 of Giomer were prepared. Subsequently, the samples were randomly divided into three solution groups (n = 15): Group 1—Sambucol Pediatric Syrup, Group 2—Hidropolivital Baby Drops, and Group 3—artificial saliva, which is preparation for patients with xerostomia. For 28 days, the specimens were immersed in 10 mL of each multivitamin for two minutes every 24 h. Color measurements were repeated on days 7, 14, 21, and 28. Statistical analysis was performed using the Jamovi software version 2.2.5, employing the Shapiro–Wilk test for normality and the Kruskal–Wallis test for non-parametric data. When comparing materials, statistically significant differences (p < 0.001) were observed between RGI and Giomer, and RGI and composite, but not between Giomer and composite (p = 0.716). The highest change was observed in RGI–Hidropolivital ΔE00 = 3.27 (2.38–4.59) and the least in composite–Sambucol ΔE00 = 0.72 (0.30–1.18). In conclusion, the exposure time and the multivitamin influence the color change of restorative materials. [ABSTRACT FROM AUTHOR]

The aim of this study was to obtain extracts of anthocyanin pigments from red and purple-fleshed potato juices characterized by stable color. For this purpose, potato juices were pasteurized at different temperatures or fruit and vegetable concentrates were added to them. Color stability tests of the obtained pigments were carried out in model pH and temperature conditions and after adding to natural yogurt. Both the pasteurization process and the addition of fruit and vegetable concentrates to the potato juices positively affected their color and its stability in time. However, the pasteurization of the potato juices had a negative effect on the content of biologically active compounds, in contrast to the juices stabilized with the addition of fruit and vegetable concentrates. Anthocyanin pigments from red-fleshed potato juices were more stable than those isolated from the purple-fleshed potato juices. The results of model tests of the anthocyanin pigment concentrates from the colored-flesh potatoes and natural yoghurts with their addition confirmed the high stability of the tested concentrates. [ABSTRACT FROM AUTHOR]

Background: To overcome the color layering procedure, monochromatic resin composites have been introduced. However, little is known about their polishability, gloss and color stability. This study aimed to investigate the surface roughness, gloss, and color change of monochromatic resin composites polished with wheel systems after being immersed in coffee. Materials and methods: Omnichroma, Zenchroma, Essentia Universal, Charisma Diamond One and NeoSpectra ST were used to obtain 120-disc samples of 8 × 2 mm. Only one side of the sample was polished with Twist Dia (TWD) or Nova Twist (NOV). The samples were examined for surface roughness, gloss, and color (ΔE and ΔE00) before and after 7 days of immersion in coffee and subsequent repolishing. The discs were examined via SEM. Surface roughness and gloss values were analyzed using ANOVA, Tukey and Pearson correlation tests. ΔE and ΔE00 values were evaluated using T tests, multivariate ANOVA, and Dunnett's post-hoc tests. Results: For TWD groups, the smoothest material was Omnichroma (p < 0.05), while for NOV groups, it was Omnichroma and Zenchroma. Omnichroma was the glossiest, while Charisma Diamond One was the least glossy. In TWD groups, Charisma Diamond One and Essentia Universal were the most discolored, while Zenchroma and Omnichroma were the least. For NOV groups, Essentia Universal and Charisma Diamond One were the most discolored, while NeoSpectra ST, Omnichroma and Zenchroma were the least. After repolishing, Charisma Diamond One did not reach the level of ΔE < 2, while the other groups showed values below. Color evaluation with the CIELab and CIEDE2000 systems revealed similar results for the TWD groups after post-staining. Conclusions: Smooth and glossy surfaces could be achieved with the wheel system regardless of the composite resin. Repolishing after discoloration ensures that the color recovery is below the acceptable limit. Color evaluations with CIELab and CIEDE2000 yielded similar results. [ABSTRACT FROM AUTHOR]

The background of this study is to evaluate the effect of soaking the base of thermoplastic nylon dentures in cinnamon extract Cinnamomum burmannii and alkaline peroxide solution on color stability, considering the importance of maintaining denture hygiene with safe and effective cleaning agents. This study aimed to evaluate the colour stability of thermoplastic nylon denture bases after immersion in Cinnamomum burmannii 20% cinnamon extract, alkaline peroxide solution, and distilled water for 4 and 8 days. This research is a laboratory experimental research. This study was conducted with Post-Test Only Control Group Design, which is research with treatment on one or more groups whose final results are compared with the control group, that the colour stability of thermoplastic nylon denture bases after immersion in Cinnamomum burmannii 20% cinnamon extract and alkaline peroxide solution had similar mean ΔE unit values, namely 2.45 ΔE ± 0.27 and 2.24 ΔE ± 0.28 for 4 days, and 2.87 ΔE ± 0.19 and 2.58 ΔE ± 0.30 for 8 days. While immersion in distilled water showed lower mean values of ΔE units, namely 1.17 ΔE ± 0.10 and 1.35 ΔE ± 0.29. Statistical test results showed that there was a significant effect on colour stability (p = 0.0001), but there was no significant difference between cinnamon extract and alkaline peroxide solution, either for 4 days (p = 0.192) or 8 days (p = 0.113). [ABSTRACT FROM AUTHOR]

Background It has been reported that using mouthwashes can discolour the surface of teeth. Their effect on the stainability of newly introduced lithium disilicate ceramics is, however, unknown. Objective: The purpose of this in vitro study was to investigate how mouth washes affected the color change of new and conventional lithium disilicate (LS2) ceramics that were finished using various techniques. Materials and Methods A total of 56 ceramic slices were produced from conventional LS2 (E Max CAD, Ivoclar) and a novel virgilite based LS2 (Cerec Tessera, Dentsply Sirona). According to the finishing method, the specimens were divided into glazed and polished subgroups. Each subgroup was further subdivided into two based on immersion in chlorhexidine (CHXD) or Listerine (LIST) mouth washes. A handheld spectrophotometer was used to measure the color attributes, and color differences (ΔE00) were then counted using specific equation. Data were analyzed using ANOVA and Tukey's post-hoc tests. Results Significant differences in color change (ΔE00) values were observed between conventional and novel LS2 ceramics, as well as between different finishing methods and mouth-rinse solutions. Chlorhexidine induced higher color differences than Listerine, with average ΔE00 values of 0.959 and 0.885, respectively (p < 0.001). The polished specimens generally exhibited higher ΔE00 values than the glazed specimens, with average values of 1.071 and 0.792 for conventional LS2, and 0.836 and 0.786 for novel LS2 (p < 0.001). However, most color changes did not exceed the perceptibility and acceptability thresholds. Conclusion Using CHXD and LIST mouth washes affected the color change of polished or glazed conventional and novel lithium disilicate ceramics. In general, the stainability of polished specimens was higher than that of glazed ones. There was more discoloration on specimens immersed in CHXD than those immersed in LIST. [ABSTRACT FROM AUTHOR]

In this research we proposed and tested a solution for improving lightfastness of paperboard electrophotographic prints – enhancing the printed material with inks containing pearlescent pigments. The goal was to analyze how pearlescent pigments’ composition and the size of their particles affect lightfastness, and to assess whether this important property is influenced by the tone value of the initial ink layer. Therefore, lightfastness of the unprinted paperboard and the paperboard printed in electrophotography with medium and full coverage of black ink was measured before and after overprinting with pearlescent inks. The results indicate that pearlescent pigments can be efficiently used to prevent light induced degradation of both paperboard and the corresponding prints. The most significant improvements in lightfastness were noticed when pearlescent inks were printed directly onto the paperboard and on the prints with 50 % black coverage. The best protection from light was achieved with pigments containing only two layers – mica and ferric oxide. Pigments containing mica, titanium dioxide, and tin oxide provided satisfactory lightfastness of the printed paperboard even with the small surface coverage. No significant correlation was found between the size of pearlescent pigment particles and the lightfastness of the paperboard prints to which they are applied. [ABSTRACT FROM AUTHOR]

Discoloration and flexural strength of denture bases are important factors affecting the comfort and durability of denture users. This study aims to determine the effect of immersion of nylon thermoplastic denture base in alkaline peroxide solution and 10% castor oil (Ricinus Communis Oil) on color stability and flexural strength. This study used a laboratory experimental design with samples of cylindrical (20 x 2 mm) thermoplastic nylon resin for color stability test and rectangular (65 x 10 x 3 mm) for flexural strength test. There were two study groups: one control group and two treatment groups immersed in alkaline peroxide and 10% castor oil solution, with two time variables, 8 days and 12 days. The total number of samples was 60, with each group having 10 samples. The color stability test used a colorimeter, and the flexural strength test used a universal testing machine. The results showed that there was no effect of soaking the nylon thermoplastic denture base in alkaline peroxide on color stability, with a value of p = 0.412 for 8 days and p = 0.179 for 12 days. In addition, there was no effect of immersion in alkaline peroxide and 10% castor oil on flexural strength, with p value = 0.076 for 8 days and p = 0.917 for 12 days. The implication of this study is that immersion in alkaline peroxide and castor oil solution does not affect the color stability or flexural strength of nylon thermoplastic denture bases, making them safe for long-term use. [ABSTRACT FROM AUTHOR]

Copyright of Current Research in Dental Sciences is the property of Ataturk University Coordinatorship of Scientific Journals and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The influence of different aluminum powder and dosage on the surface leveling, gloss and metal effect of the metallic powder coating has been investigated. Meanwhile, the effects of different polyester resin, additives (e.g., leveling agent, brightener, aluminum powder arrangement dispersant, etc.), extrusion processes, bonding processes, etc., on the metal effect of coating surface and the improvement of surface defects are discussed. It provides the theoretical basis for the production of metallic powder coatings and the solutions for the treatment of surface defects so as to ensure the quality of products. [ABSTRACT FROM AUTHOR]

Background: There is a lack of studies comparing the dimensional accuracy and color stability of denture base resins made using computer-aided design and computer-aided manufacturing (CAD-CAM) milling, 3-dimensional (3D) printing, and conventional denture processing techniques. This makes it challenging to determine the best method to fabricate complete dentures. The objective of this in vitro investigation was to assess and contrast the color stability and dimensional accuracy of denture base resins that were 3D printed and CAD-CAM milled, both before and after aging by thermocycling using digital surface matching technology and a benchtop laser scanner without using a spray, to optimize adaptation of the denture base and cast to minimize any imperfections and to evaluate the impact of the denture cleansing solution on the stability of color. Methods: Evaluation of the dimensional accuracy (n = 27) was completed on a sectional maxillary stone cast using a digital 3D-surface matching software before and after 5000 thermocycles. A spectrophotometer was used to measure the color change (△E00) of all disc specimens (N = 54) before and after 500 thermocycles and immersion in denture cleansing solution for 30 cycles (3 min each) daily for 6 days. The Kruskal Wallis test, Dunn's post hoc test, Tukey's test with Bonferroni adjustment, one sample t test and independent t test were used to statistically analyze the data (α < 0.05). Results: Thermocycling decreased the dimensional accuracy of the heat polymerized group at all 5 locations and the 3D-printed group at locations 1, 3 and 5 (P >.05), while it had no significant difference on the CAD-CAM milled group at all locations (P <.05). The color change (△E00) was lowest in the CAD-CAM milled group, moderate in the heat-polymerized group and highest in the 3D-printed group. After immersion in denture cleanser, the color change (△E00) was significantly higher in the 3 groups compared with after thermocycling (P >.001). Conclusions: CAD-CAM milled resins had the highest dimensional accuracy and the best color stability, conventional heat polymerized acrylic resins showed moderate change in dimensional accuracy and color stability, while the 3D- printed resin had the lowest dimensional accuracy and color stability after aging by thermocycling. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Material and Methods Results Conclusion Clinical Significance To evaluate the effect of different modeling agents on color changes, surface roughness, and translucency parameters over time in Bulkfill resin composites.Sixty specimens were prepared using three Bulkfill resin composites (Tetric N‐Ceram Bulkfill, Filtek One Bulkfill and Opus Bulkfill) and three modeling agents (Wetting Resin, Optibond FL and Ambar APS). All specimens were subjected to a simulated tooth‐brushing (Baseline, 50.000 cycles, 100.000 cycles), and surface roughness was measured at each interval. Surface topography was evaluated. The translucency parameter and color changes were assessed after 24‐h, 7‐, 14‐ and 30‐day immersion in water, wine, and coffee. Data was analyzed using ANOVA and Bonferroni test.All specimens increased roughness after simulated tooth‐brushing (p < 0.05). Wetting Resin decreased roughness on Tetric N‐Ceram Bulkfill (p < 0.05). The translucency parameter remained unaltered for all groups. All groups changed color after 30‐days of immersion in wine and coffee (p < 0.05). Ambar APS and Wetting Resin on Tetric N‐Ceram Bulkfill showed higher color changes when immersed in coffee (p < 0.05).The use of modeling agents does not jeopardize translucency properties but may affect surface roughness and color properties of Bulkfill resin composites depending on their composition.The findings of this study suggest that surface roughness and color properties are affected by the differences in the composition between modeling agents and Bulkfill resins composites. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study examined how piranha solution affects denture base acrylic resin color stability. Twenty acrylic resin specimens (disc shape, 20 mm diameter, 2 mm thick) were made for color stability. The specimens were randomly divided into Group W (no treatment) and Group P (piranha solution treatment). Color stability is measured with Photoshop. The data was analyzed using a T-test. There was significant variance in group P values (P ≤ 0.05). Compared to Group W, the Piranha solution treatment group (Group P) affected color value (L), hue (a), and chroma (b). This study found that the piranha solution can modify the color of heat cure acrylic surface qualities. [ABSTRACT FROM AUTHOR]

The purpose of this study was evaluating the performance of new Bis-EFMA based bulk-fill composites with common methacrylate based composites and commercial dental composites. The Bis-EFMA monomer was synthesized and the novel Bis-EFMA based bulk-fill composites were prepared. The resin composite samples were co-cultured with human gingival epithelial cells and human dental pulp stem cells to test the biocompatibility. The edge adaptation was observed under a combination of stereoscope and scanning electron microscope. The internal hardness was measured using a Vickers microhardness tester after one-time filling of cavities prepared in extracted teeth. After friction and wear test on the surface of the resin composites, the surface morphology and volume wear of each group were measured by the optical profilometer. The color stability was measured by a colorimeter. Direct contact with human gingival epithelial cells and human dental pulp stem cells did not cause significant changes in their growth density and morphology, indicating good biocompatibility of Bis-EFMA group (p > 0.05). The continuous margin proportion of the Bis-EFMA group was as good as commercial bulk-fill composites (p > 0.05). The sectional microhardness results showed that the Bis-EFMA group had the highest microhardness. After the friction and wear test, the volume wear of the Bis-EFMA group was minimal, indicating its good wear resistance and mechanical strength. Color changes in all resin groups after 28 days of immersion were within the clinically acceptable range. The addition of Bis-EFMA demonstrated excellent biocompatibility, edge adaptation and color stability comparable to commonly used clinical bulk-fill composites, along with preferable mechanical strength, friction and wear resistance. Bis-EFMA based bulk-fill composites have the potential to be employed as a bulk filling material in commercial dental composite applications. • Bis-EFMA BF-DRCs showed good biocompatibility to the pulp periodontal tissue. • Bis-EFMA BF-DRCs adapted well to cavity wall. • The rigid structure got Bis-EFMA BF-DRCs higher microhardness and anti-friction property compared with SDR™. • Bis-EFMA BF-DRCs had reliable color stability. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the influence of different mouthwash solutions on the color stability of a nanohybrid composite resin. Forty discs of Luna nanohybrid composite resin were prepared and randomly assigned to 4 experimental groups (n = 10), determined by the type of immersion solution: distiiled water (DW); Oral-B Pro-Health mouthwash (OBPH); Listerine Total Care mouthwash (LTC); or Colgate Plax Infinity mouthwash (CPI). The discs were immersed in solution for 30 minutes a day and stored at 37°C for 24 hours. Digital photographs of each specimen were taken at each timepoint and transferred to a computer program for color analysis. The International Commission on Illumination L*a*b* system was used to analyze the color of the specimens at baseline and the overall color change (ΔE*) at baseline, 30 days, 60 days, and 90 days. Two-way analysis of variance was used to evaluate the influence of solution and time on 82 values (α = 0.05). The f test was used as a post hoc test to compare the mean values between groups (α = 0.05). After 30 days, all groups showed small color change values compared with baseline (ΔE*1 < 1.0). However, after 60 days, the LTC and CPI groups showed greater color change (ΔE*2) than the other groups, and the difference was statistically significant (P < 0.05). After 90 days, all groups differed significantly compared with the control group (P < 0.05), and all mouthwash groups presented color change values that are considered clinically unacceptable (ΔE*3 > 3.0). The results of this in vitro study indicate that mouthwash solutions do not cause significant color changes in nanohybrid composite resin for a period of up to 30 days; however, longer periods (90 days) of exposure could make the restorative material esthetically unacceptable. [ABSTRACT FROM AUTHOR]

Background: Charcoal-containing mouthwashes have become popular in society; however, there is inadequate evidence of their effect on composite restorations' color stability. This study evaluates the effect of two charcoal-containing mouthwashes on the color stability of two composite resins. Methods: Disk-shaped (6x2 mm) composite resins (Filtek Universal Restorative (FU) and G-ænial Anterior (GC)), each (n = 30), were prepared. Baseline color values were measured using a spectrophotometer. After six months of storage in distilled water, randomly assigned samples were subjected to a 12 h immersion in either distilled water (control group), Natural Mouthwash Charcoal, or Colgate Plax White+Charcoal (n = 10). Then, color values were re-measured, and color change (ΔE00) values were computed. Two-way analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) multiple comparison tests were used to compare mean ΔE00 values of composite resin materials (P < .05). Results: ΔE00 values of FU exposed to Natural Mouthwash Charcoal were significantly lower compared with other mouthwash groups and the controls. There were no significant differences in ΔE00 values among the GC specimens placed in different immersion media (P > .05). No statistically significant difference was observed regarding color change between composite restorative materials. ΔE00 values for the restorative materials were above the acceptability threshold of 1.8 for all groups. Conclusion: Charcoal-containing mouthwashes caused unacceptable color changes in aged composites. In most groups, the color change was not significantly different from that in distilled water. The color change of FU immersed in Natural Mouthwash Charcoal was less than that in distilled water. Charcoal-containing mouthwashes can be considered part of daily oral hygiene practices. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study is to evaluate and compare the color stability of nanoparticles reinforced maxillofacial silicone after disinfection with neutral soap, 4% chlorhexidine, and ozone water. Materials and Methods: According to ISO 4823, a metal die was fabricated, and 96 samples were created using Room Temperature Vulcanizing silicone (RTV), Heat Temperature Vulcanizing silicone (HTV), and 3% silicone dioxide nanoparticle-reinforced RTV and HTV silicones. The samples were disinfected using neutral soap, 4% chlorhexidine, and ozone water for 10 minutes, three times a day, for 60 days. The samples were divided into four groups: Group 1 (RTV), Group 2 (3% SiO2 nanoparticle-reinforced RTV), Group 3 (HTV), and Group 4 (3% SiO2 nanoparticle-reinforced HTV). The color stability of the maxillofacial silicones was evaluated before and after disinfection using a UV spectrophotometer. The obtained color stability values were statistically analyzed using two-way ANOVA and Tukey's HSD test. Values were considered significant when p<0.05. Results: The 3% SiO2 nanoparticle-reinforced HTV silicone showed better color stability compared to HTV and RTV silicones, with the least difference observed in the 3% SiO2 nanoparticle-reinforced RTV. Conclusion: Ozone water caused the least change in the color of maxillofacial silicone compared to other disinfectant solutions. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the surface roughness (SR) and color changes of single‐shade and nanohybrid resin‐based restorative materials (RBC) after immersion in liquids at different pH values. For RBCs, a total of 120 specimens, 30 for each material, were prepared using 10 mm diameter and 2 mm thick molds. For flowable bulk fill RBC, a total of 40 specimens, 10 for each material, were prepared using 10 mm diameter and 4 mm thick molds (n = 10). After initial color and SR measurements, samples were stored in the liquids for 14 days and all of the measurements were repeated on 14th days. Scanning electron microscopy and atomic force microscopy analyzes were performed in all groups. When SR results are examined; among all liquids, the highest SR value was observed in the Carisma Diamond One (CDO) group, while the lowest SR value was observed in the Omnichroma Flow Bulk (OMF) group (p <.05). When the color changes (ΔE) results are examined; it was observed that CDO group had highest color change and OMF group had the lowest values. It has been observed that among the liquids, the liquids that affect the ΔE values of the materials the most are coffee and cola. When the ΔE values of the subgroups of the materials were examined, there was a statistically significant difference in all subgroups of RBCs (p <.05). While acidic liquids increased the SR of RBCs, coffee more affected the color change of RBCs. Research Highlights: Clinicians should keep in mind that the RBCs tested may change their surface properties and colors when exposed to various liquids. People who have RBCs should pay attention to the consumption of acidic and highly pigmented liquids. [ABSTRACT FROM AUTHOR]

The color stability and quality changes of red pepper powder of various initial moisture content (7%, 10%, and 13%) and packaged with different materials, low-density polyethylene (LDPE) and nylon layered polyethylene (Ny/PE) film pouches or plastic and glass bottles, were compared during storage at 20 °C for 126 days. In the 7% moisture content sample packaged in LDPE film and plastic bottles, the L* and b*-values increased from 48.2 ± 0.7 and 15.4 ± 1.1 to 65.2–65.9 and 29.5–30.3, respectively, while the a*-value decreased from 26.1 ± 0.7 to 14.2–15.9, indicating a noticeable color change from red to orange. However, the decrease in the capsaicinoid and free sugar content of red pepper powder over time was found to have no significant correlation with moisture content and packaging type. As a result, the color change during the long-term storage of red pepper powder was greatly influenced by the initial moisture content and gas permeability of the packaging material. [ABSTRACT FROM AUTHOR]

Esthetically pleasing temporary prostheses are often necessary for extended periods in a variety of clinical scenarios. Adjustments to the occlusion or margins are commonly needed before cementing the temporary prosthesis. Therefore, it is clinically necessary to repolish the rough surface to avoid biological and esthetic issues associated with rough surfaces. The purpose of this in vitro study was to assess and compare the impact of various polishing protocols on the surface roughness and color stability of three resin materials used for provisional crowns. A total of 150 specimens were fabricated from auto-polymerizing polymethyl methacrylate, bis-acryl composite, and Methyl methacrylate-LC resin using a stainless steel mold. Each material group was divided into five groups (n = 10) based on the applied surface treatment: positive control group (G1): no roughening or surface treatment, Negative control group (G2): acrylic bur-roughened surface without any polishing, the different surface treatment groups of silicon carbide and aluminum oxide stone polishing (G3), diamond-coated rubber twist (G4), and Surface Glaze (G5). An optical profilometer was used to assess the surface roughness of all samples. After undergoing 6000 cycles of thermocycling followed by immersion in a coffee solution for 15 days at 37 °C, color parameters were measured using a spectrophotometer both before and after a storage period to evaluate color differences. A two-way ANOVA test with α = 0.05 significance level was carried out to determine the impacts of both the materials utilized and the polishing protocol. Among the three types of resin examined, the bisacryl group exhibited superior surface quality in positive control groups, while PMMA resin demonstrated higher polishability. The diamond-coated rubber twits resulted in lower Ra values of 0.36 (0.01) µm, 0.52 (0.11) µm, and 0.28 (0.05) µm for PMMA, BAMA, and MMLC resins, respectively. The application of photo-polymerized surface glaze led to a plaque accumulation threshold of 0.2 µm across all resin groups. The greatest mean color change occurred in the negative control group, indicating a propensity for more staining on rougher surfaces. The Bisacryl resin exhibited higher ΔE values, whereas PMMA showed better color stability. The lowest ΔE values were found when the surface glaze was applied to all of the provisional crown resins. Untreated Bisacryl resin exhibited the lowest Ra values, while PMMA resins demonstrated superior surface morphology after polishing. PMMA provisional crown resins showed increased resistance to staining. The use of surface glaze enhanced both smoothness and color stability on the surfaces. [ABSTRACT FROM AUTHOR]

In this work, based on an analysis of the structure–property relationship, stabilizing components have been selected that can effectively participate in the suppression of certain destructive processes in polymers. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to examine how staining with coffee affects single-shade universal resin composites and a multi shade universal resin composite in terms of translucency and color stability.Method: Five different resin composites (Omnichroma, Vittra APS Unique, Zenchroma, Charisma Diamond One, and Neo Spectra ST) were used to create 50 samples (n=10). A spectrophotometer was used to record translucency parameter (TP00) and color changes ( ΔE00) at baseline and after immersion in coffee for 24 h. Color differences were calculated according to CIEDE2000. Data analysis was performed using one-way ANOVA and the paired-samples t-test. Results: After immersion of resin composite samples in coffee for 24 h the Vittra APS Unique group showed the highest ΔE00 value and the Neo Spectra ST group the lowest (P

Abstract Background To overcome the color layering procedure, monochromatic resin composites have been introduced. However, little is known about their polishability, gloss and color stability. This study aimed to investigate the surface roughness, gloss, and color change of monochromatic resin composites polished with wheel systems after being immersed in coffee. Materials and methods Omnichroma, Zenchroma, Essentia Universal, Charisma Diamond One and NeoSpectra ST were used to obtain 120-disc samples of 8 × 2 mm. Only one side of the sample was polished with Twist Dia (TWD) or Nova Twist (NOV). The samples were examined for surface roughness, gloss, and color (ΔE and ΔE00) before and after 7 days of immersion in coffee and subsequent repolishing. The discs were examined via SEM. Surface roughness and gloss values were analyzed using ANOVA, Tukey and Pearson correlation tests. ΔE and ΔE00 values were evaluated using T tests, multivariate ANOVA, and Dunnett’s post-hoc tests. Results For TWD groups, the smoothest material was Omnichroma (p

Signal transducer and activator of transcription 3 (STAT3) exists in the cytoplasm, nucleus, mitochondria, and mitochondria associated endoplasmic reticulum membranes, which is a signal transduction protein involved in various physiological processes such as cell proliferation, differentiation, migration, and immune regulation. This article provides an overview of the structures and types of STAT3 and the pathways through which STAT3 enters mitochondria, and elaborates on the regulatory effect of STAT3 on cellular homeostasis including the anti-apoptotic effect mediated by endoplasmic reticulum Ca2+ transport, the mechanism of action in maintaining mitochondrial function, and the regulatory mechanism on lipid synthesis and catabolism. Furthermore, this paper explores the regulatory mechanism of STAT3 on meat color from the perspective of regulating hematopoietic stem cells, skeletal muscle, mitochondrial homeostasis, and lipid synthesis and metabolism in order to provide a theoretical reference for improving meat color.

Abstract Background There is a lack of studies comparing the dimensional accuracy and color stability of denture base resins made using computer-aided design and computer-aided manufacturing (CAD-CAM) milling, 3-dimensional (3D) printing, and conventional denture processing techniques. This makes it challenging to determine the best method to fabricate complete dentures. The objective of this in vitro investigation was to assess and contrast the color stability and dimensional accuracy of denture base resins that were 3D printed and CAD-CAM milled, both before and after aging by thermocycling using digital surface matching technology and a benchtop laser scanner without using a spray, to optimize adaptation of the denture base and cast to minimize any imperfections and to evaluate the impact of the denture cleansing solution on the stability of color. Methods Evaluation of the dimensional accuracy (n = 27) was completed on a sectional maxillary stone cast using a digital 3D-surface matching software before and after 5000 thermocycles. A spectrophotometer was used to measure the color change (△E00) of all disc specimens (N = 54) before and after 500 thermocycles and immersion in denture cleansing solution for 30 cycles (3 min each) daily for 6 days. The Kruskal Wallis test, Dunn’s post hoc test, Tukey’s test with Bonferroni adjustment, one sample t test and independent t test were used to statistically analyze the data (α .05), while it had no significant difference on the CAD-CAM milled group at all locations (P .001). Conclusions CAD-CAM milled resins had the highest dimensional accuracy and the best color stability, conventional heat polymerized acrylic resins showed moderate change in dimensional accuracy and color stability, while the 3D- printed resin had the lowest dimensional accuracy and color stability after aging by thermocycling.

Caesalpinia sappan L (CS) heartwood is used as a natural red colorant in several Asian ethnic traditional drinks both as sole ingredient or mixed with other herbs. However, the pigment is unstable and easily degraded during storage which affects consumer acceptance. This research aimed to investigate the effect of different blanching and drying methods on the color stability, brazilin content, and antioxidant activity of CS heartwood drinks. Steam blanching, water blanching, sun drying and cabinet drying were examined in this study. The most common method applied in traditional production, without blanching and sun drying, was used as a control. The experimental design used was complete randomized design with triplicates. Data are presented as mean ± standard deviation and analyzed by SPSS statistics version 20. The results showed that blanching and drying methods affected the color intensity. For a pure CS heartwood herbal drink, the sample prepared with water blanching and cabinet drying (BCD) showed the highest red value, leading to a 48 % improvement compared to the control. This red value is in accordance with the brazilin content. Sample BCD showed the highest brazilin content, which was 376 % higher than that of the control. Similarly, the BCD sample had the highest antioxidant activity and total phenolic content, with IC50 values of 98.99 ppm and 213.12 mg GAE g-1, respectively. This result revealed that brazilin might act as an antioxidant. Similar to the pure CS drink, the highest quality of mixed herbal drink was obtained by BCD sample. The results suggest that the combination of water blanching and cabinet drying (BCD) was the best method to improves the quality of CS heartwood drink both in pure and mixed herbal drinks as a functional drink. [ABSTRACT FROM AUTHOR]

In recent years, there has been a growing interest in advanced packaging films made from natural polymers. These films are integrated with pH-sensitive dyes, aiming to monitor the freshness of food. Specifically, the development of pH-adaptive intelligent packaging films, known as MC5/ZA5-Anth3%, involves using methylcellulose (MC) and zinc alginate (ZA) as the foundational materials, with anthocyanins (Anth) serving as the freshness indicators. The production of MC5/ZA5-Anth3% films has resulted in improved thermal stability, mechanical properties and water resistance, alongside a reduction in the transmission of ultraviolet–visible (UV–vis) light through the material. Importantly, these color-changing films undergo a noticeable change in color when subjected to pH changes or exposure to ammonia gas, making them suitable for detecting shifts in the pH of foods like pork and shrimp, the presence of volatile nitrogen compounds, and early signs of food degradation. Upon exposure to varying pH buffers, the color indicator film underwent a noticeable transition from a reddish-pink hue to blue, ultimately shifting to blue-green. Consequently, this pH-sensitive color indicator film emerges as a viable candidate for the smart, real-time monitoring of freshness in perishable foods such as pork and shrimp. [ABSTRACT FROM AUTHOR]

Abstract Background To evaluate the effect of staining beverages on the color-changing of resin-infiltrated artificial white spot lesions (WSLs). Methods Thirty-five artificial WSLs were created by pH cycling on flat bovine teeth specimens. The WSLs were treated with resin infiltration and were divided into five groups based on staining beverages: artificial saliva, coffee, wine, green tea, and Coca-Cola. These specimens were subjected to a 28-day exposure to the respective beverages. Color stability was assessed using a spectrophotometer at different time points: baseline, after 7, 14, 21, and 28 days of exposure, and repolishing. The color difference (∆E) between each time point and the baseline was calculated. Statistical analysis was performed using two-way measures ANOVA with a significance level of p = 0.05. Results All resin-infiltrated specimens exposed to staining beverages for 7 days exhibited more significant color changes than those exposed to artificial saliva. The color change patterns varied based on the type of beverage. The color alterations intensified with extended immersion in the wine and Coca-Cola groups, while there were no significant differences in the color of specimens after 28 days of immersion in the coffee and green tea groups. However, after cleaning with pumice powder, all specimens showed significantly reduced color changes compared to those observed after 28 days of immersion, except those immersed in coffee. Conclusions Exposure of resin-infiltrated bovine tooth specimens to staining beverages resulted in a significant color alteration as the immersion time increased. However, the staining effect could be minimized by cleaning with pumice powder, except for the coffee group. Clinical relevance After resin infiltration treatment, patients should be advised to minimize the consumption of colored beverages to prevent staining that could impact esthetic appearance.

Abstract Background Patients tend to favor the whitening mouthwashes as they are easily applied and affordable. This study aimed to evaluate the effect of hydrogen peroxide versus charcoal-based whitening mouthwashes on color, surface roughness, and color stability of enamel. In the current study, the whitening mouthwashes used have the ability to stop future stains due to their white seal technology. Methods A total of 21 permanent central incisor teeth extracted for periodontal reasons were used in the present study. Teeth roots were sectioned and crowns were mounted in self-cured acrylic resin blocks. The specimens were randomly divided into three groups (n = 7) according to the tested whitening mouthwash: Control group ‟ DW” (Distilled water), ‟OW” group: Peroxide-based mouthwash (Colgate Optic White) and ‟CP” group: Charcoal-based mouthwash (Colgate® Plax Charcoal). Regarding ‟OW” and ‟CP” groups, the specimens were immersed in 20 ml of the tested mouthwash in each corresponding group for 1 min twice daily (morning and evening) for a total of 12 uninterrupted weeks. Color change was assessed using VITA Easyshade spectrophotometer and surface roughness (Ra) was measured using a white light interferometer. The specimens were stained using black tea solution and color was measured after 24 h of immersion for assessment of color stability. Results Color change results revealed that both whitening mouthwashes were able to restore color comparable to the control group with no significant difference between them. Regarding surface roughness, the control group showed the highest mean Ra value, followed by ‟OW” group while ‟CP” group showed the lowest mean Ra value. While color stability after staining, the control group showed a significantly higher value than the ‟CP” and ‟OW” groups. Conclusion Hydrogen peroxide and charcoal-based whitening mouthwashes improve the color of enamel with no adverse effect on the surface roughness. Both whitening mouthwashes were beneficial to maintain the color after staining and prevent future enamel stains.

Aim: This study investigates the interaction of zirconia and polyetheretherketone (PEEK) with indirect composite in fixed dental prostheses. This investigation aimed to assess the shear bond strength (SBS) and color stability of zirconia and PEEK before and after aging, addressing critical concerns in dental restorative applications. Settings and Design: The current in vitro study used 96 samples, 48 of which were divided into two groups, zirconia and PEEK, before and after thermocycling. A dual-axis chewing simulator was used for thermocycling. SBS was measured using a universal testing machine, and color stability was checked using a reflective spectrophotometer. Materials and Methods: Ninety-six samples were categorized into zirconia and PEEK groups, each with subgroups undergoing thermocycling. Samples were prepared using computer-aided design/computer-aided manufacturing milling and veneered with composite resin. Thermocycling involved 10,000 cycles, simulating stress levels equivalent to approximately 1 year of clinical use. SBS was assessed using standardized tests. Stereomicroscopic analysis was performed to evaluate the type of failure. Color stability of the core materials with indirect composite was done using a spectrophotometer before and after aging. Statistical Analysis Used: Statistical analysis included paired t-tests and independent t-tests in SPSS software. Results: The results revealed that SBS values for composite on PEEK decreased from 13.86 ± 0.164 MPa before thermocycling to 13.46 ± 0.185 MPa after thermocycling, with a significant difference (P < 0.005). However, both pre- and postthermocycling values for PEEK were higher than zirconia. The t-test confirmed the lower bond strength of composite to zirconia, with a noteworthy improvement after aging. Stereomicroscopic images revealed adhesive failure for the zirconia group and mixed (adhesive and cohesive) failure for the PEEK group. ΔE values were 3.21 ± 0.127 and 2.93 ± 0.142 for zirconia and PEEK groups, respectively (P < 0.005). Conclusion: Within the limitations of this study, it can be deduced that PEEK is a feasible substitute for zirconia when used in conjunction with indirect composite for the fabrication of dental prostheses.

Abstract Background This study aimed to investigate the effect of whitening toothpastes on the color stability and surface roughness of resin composites stained with coffee and cigarette smoke. Methods Seventy-two disk-shaped specimens (6 × 2 mm) of suprananohybrid resin composite were randomly divided into two groups and exposed to coffee and cigarette smoke (n = 36). After staining, the samples randomly divided into four groups according to whitening toothpastes and were brushed for 4 min: Opalescence Whitening (OW); Colgate Optic White (COW); Curaprox Black is White (CPX) and, distilled water (control) (n = 9). Color was measured with spectrophotometer at the initial, after staining, and after brushing, and surface roughness was measured with profilometer at the initial and after brushing. A surface morphology analysis was examined using scanning electron microscopy and atomic force microscopy. The obtained data were statistically analyzed. (p

Abstract Objective To determine the effects of conventional cigarette smoking (CS) and recent heated tobacco products (HTPs) on the surface roughness and color stability of different indirect restorative materials. Materials and methods One hundred disc-shaped samples were constructed of three different restorative CAD/CAM materials: lithium disilicate glass–ceramic (IPS e.max CAD; Ivoclar Vivadent, Liechtenstein), zirconia (BruxZir® Zirconia, Glidewell, USA) and polyetheretherketone (BioHPP® bredent GmbH, Germany). Of the IPS e.max CAD and the Bruxzir samples, 20 samples were glazed, and 20 samples were polished, while the BioHPP samples were all polished according to the manufacturer’s instructions. Fifty samples were subjected to conventional cigarette smoking (LM, Philip Morris International Inc., Egypt) (Groups: IPS e.max CAD_Glazed exposed to CS (LD_G_Cig), IPS e.max CAD_Polished exposed to CS (LD_P_Cig), Bruxzir_Glazed exposed to CS (Zr_G_Cig), Bruxzir _Polished exposed to CS (Zr_P_Cig) and BioHPP exposed to CS (PEEK_Cig) and fifty samples were exposed to heated tobacco product smoking (Heets, Russet selection, Philip Morris International Inc., Italy) (Groups: IPS e.max CAD_Glazed exposed to HTP (LD_G_HTP), IPS e.max CAD_Polished exposed to HTP (LD_P_HTP), Bruxzir_Glazed exposed to HTP (Zr_G_HTP), Bruxzir CAD_Polished exposed to HTP (Zr_P_HTP) and BioHPP exposed to HTP (PEEK_HTP).. Six hundred cigarettes/heets representing 30 days of medium smoking behavior (20 cigarettes/day) were used. Before and after exposure to smoke, the surface roughness of all the samples was measured using JITAI8101 surface roughness tester (Beijing Jitai Tech Detection Device Co., Ltd, China, and the color parameters were assessed using VITA Easyshade Advance 4.01 (VITA shade, VITA made, VITA). The data were analyzed using One-way ANOVA, paired sample t-test and independent sample t-test. The significance level was set at α

Haidar Alalawi,1 Sarah Al-Qanas,2 Sarah Al-Ghamdi,2 Raghad Al-Fuhaid,2 Soban Khan,3 Maram A AlGhamdi,1 Khalid S Almulhim,4 Faisal E Aljofi,5 Zahid A Khan,1 Yousif A Al-Dulaijan1 1Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia; 2College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia; 3Department of Dental Education, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia; 4Department of Restorative Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia; 5Department of Preventive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi ArabiaCorrespondence: Yousif A Al-Dulaijan, Department of Substitutive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia, Tel +966 13 333 1462, Email yaaldulaijan@iau.edu.saPurpose: This in vitro study investigated the effects of dietary solvents on the microhardness and color stability of CAD/CAM provisional restorations compared to conventional materials.Methods: Disc-shaped specimens (n=200) were fabricated from self-cured acrylic resin, two 3D-printing resins (FormLabs, NextDent), and a milled material (TelioCAD). Randomization assigned specimens (n=10/group) to immersion solutions: artificial saliva, citric acid, heptane, coffee, and tea. Microhardness and color stability were evaluated. One-way and three-way ANOVA with Tukey’s post hoc test analyzed the data.Results: Dietary solvents significantly reduced the surface microhardness of all tested materials (p< 0.05). Unpolished surfaces exhibited greater color changes compared to polished ones (p< 0.05) across all materials. Coffee and tea induced the most substantial reductions in hardness and the most significant color alterations (p< 0.05), whereas saliva and citric acid had minimal effects.Conclusion: Milled provisional restorations exhibited superior hardness and color stability. Dietary solvents significantly affected material properties over time, highlighting the importance of material selection for clinical applications.Keywords: 3D-printed, color stability, food, microhardness, milled, self-cure resin

This study aimed to compare the color changes in two different orthodontic clear aligner systems after submersion in various beverages for 14 days. The tested aligner systems were Taglus Premium made of polyethylene terephthalate glycol (the TAG group) and CA® Prodin+ made of a transparent copolyester and a thermoplastic elastomer (the PRO group). A total of 56 samples were firstly divided into two groups according to the tested system—TAG and PRO. Each group was subsequently divided in four subgroups according to immersion solution: A—artificial saliva, B—cola, C—coffee, D—red wine. Color measurements were performed on Days 1, 7 and 14 using a portable colorimeter and the CIE L*a*b* system. The obtained results showed significant color changes in both materials when exposed to coffee and red wine (p > 0.05). Samples in the PRO group showed a greater susceptibility to discoloration (higher ΔE values) when compared to the TAG group after submersion in cola (p = 0.025), coffee (p = 0.005) and red wine (p = 0.041) solutions. Statistical analysis revealed that all of the color parameters ΔL*, Δa*, Δb* and ΔE of both tested materials were affected by submersion in coffee solution for 14 days. In conclusion, the CA® Pro+ aligner system is more prone to staining compared to the Taglus material after submersion for 14 days in cola, coffee and red wine solutions. Submersion for 14 days in coffee solution alters all of the color parameters (ΔL, Δa, Δb and ΔE) of both tested aligner materials. [ABSTRACT FROM AUTHOR]

Color stability is crucial for dental materials to ensure they perfectly match a patient's tooth color. This is particularly challenging in photoresist-based additive manufacturing. Although some studies have addressed this issue, the exact causes of discoloration and ways to minimize it remain unclear. In this study, the intrinsic causes of discoloration in materials intended for 3D printing are investigated by examining thin-film samples (1200 µm) of various compositions, which are stored under different conditions. The samples are evaluated by measuring the UV-Vis absorption spectra at regular intervals to monitor changes. The findings reveal that both the composition of the formulations and the storage conditions significantly influence the discoloration behavior. Furthermore, methods have been developed to reduce or completely prevent discoloration. The use of photoinitiators with sterically demanding benzoyl moieties, as well as the addition of stabilizers, effectively decreases the intensity of emerging discoloration. Furthermore, incorporating the oxidizing agent cumene hydroperoxide (CHP) results in materials that maintain color stability. [ABSTRACT FROM AUTHOR]

Background: To evaluate the effect of staining beverages on the color-changing of resin-infiltrated artificial white spot lesions (WSLs). Methods: Thirty-five artificial WSLs were created by pH cycling on flat bovine teeth specimens. The WSLs were treated with resin infiltration and were divided into five groups based on staining beverages: artificial saliva, coffee, wine, green tea, and Coca-Cola. These specimens were subjected to a 28-day exposure to the respective beverages. Color stability was assessed using a spectrophotometer at different time points: baseline, after 7, 14, 21, and 28 days of exposure, and repolishing. The color difference (∆E) between each time point and the baseline was calculated. Statistical analysis was performed using two-way measures ANOVA with a significance level of p = 0.05. Results: All resin-infiltrated specimens exposed to staining beverages for 7 days exhibited more significant color changes than those exposed to artificial saliva. The color change patterns varied based on the type of beverage. The color alterations intensified with extended immersion in the wine and Coca-Cola groups, while there were no significant differences in the color of specimens after 28 days of immersion in the coffee and green tea groups. However, after cleaning with pumice powder, all specimens showed significantly reduced color changes compared to those observed after 28 days of immersion, except those immersed in coffee. Conclusions: Exposure of resin-infiltrated bovine tooth specimens to staining beverages resulted in a significant color alteration as the immersion time increased. However, the staining effect could be minimized by cleaning with pumice powder, except for the coffee group. Clinical relevance: After resin infiltration treatment, patients should be advised to minimize the consumption of colored beverages to prevent staining that could impact esthetic appearance. [ABSTRACT FROM AUTHOR]

Background: Patients tend to favor the whitening mouthwashes as they are easily applied and affordable. This study aimed to evaluate the effect of hydrogen peroxide versus charcoal-based whitening mouthwashes on color, surface roughness, and color stability of enamel. In the current study, the whitening mouthwashes used have the ability to stop future stains due to their white seal technology. Methods: A total of 21 permanent central incisor teeth extracted for periodontal reasons were used in the present study. Teeth roots were sectioned and crowns were mounted in self-cured acrylic resin blocks. The specimens were randomly divided into three groups (n = 7) according to the tested whitening mouthwash: Control group ‟ DW" (Distilled water), ‟OW" group: Peroxide-based mouthwash (Colgate Optic White) and ‟CP" group: Charcoal-based mouthwash (Colgate® Plax Charcoal). Regarding ‟OW" and ‟CP" groups, the specimens were immersed in 20 ml of the tested mouthwash in each corresponding group for 1 min twice daily (morning and evening) for a total of 12 uninterrupted weeks. Color change was assessed using VITA Easyshade spectrophotometer and surface roughness (Ra) was measured using a white light interferometer. The specimens were stained using black tea solution and color was measured after 24 h of immersion for assessment of color stability. Results: Color change results revealed that both whitening mouthwashes were able to restore color comparable to the control group with no significant difference between them. Regarding surface roughness, the control group showed the highest mean Ra value, followed by ‟OW" group while ‟CP" group showed the lowest mean Ra value. While color stability after staining, the control group showed a significantly higher value than the ‟CP" and ‟OW" groups. Conclusion: Hydrogen peroxide and charcoal-based whitening mouthwashes improve the color of enamel with no adverse effect on the surface roughness. Both whitening mouthwashes were beneficial to maintain the color after staining and prevent future enamel stains. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the staining sensitivity and surface changes in recent composite resins (Herculite Ultra XRV (Kerr, Bolzano, Italy), G-ænial A'CHORD (GC Corp, Tokyo, Japan), and Omnichroma (Yamaguchi, Japan)) when exposed to common beverages such as coffee, red wine, and Coca-Cola. A total of 60 disk-shaped specimens were prepared from three different resin composites (n = 20 each). The specimens were exposed to coffee, red wine, and Coca-Cola for 10 days. Color measurements were taken using a spectrophotometer, and surface morphology and elemental composition were analyzed using SEM and EDS. The SEM and EDS analyses revealed significant changes in the surface morphology and elemental composition of the composites after immersion. Coffee and wine caused significant surface degradation, whereas Coca-Cola resulted in the greatest degree of surface and elemental variations. Color changes (ΔE = 4 ± 0.52) were most notable in Coca-Cola for Herculite Ultra XRV (Kerr, Italy), in red wine for G-ænial A'CHORD (GC Corp, Japan) (ΔE = 12.51 ± 0.38), and in coffee for Omnichroma (Yamaguchi, Japan) (ΔE = 10.85 ± 1.03). The tested beverages significantly affected both the surface condition and the chemical composition of the resin at the surface level. These findings highlight the importance of understanding the effects of common dietary beverages on dental composites. [ABSTRACT FROM AUTHOR]

Dental restorations must replicate the natural appearance of teeth while ensuring biocompatibility and durability. This study evaluated the surface characteristics and color stability of three dental composites—Herculite Ultra XRV, G-ænial A'CHORD, and Omnichroma—exposed to acidic beverages (red wine, black coffee, and Coca-Cola). Sixty disk-shaped specimens were prepared, polished, and immersed in these beverages. Surface roughness was assessed using profilometry and SEM analysis, hydrophobicity via contact angle analysis, and surface charge through streaming potential measurements. Color stability was evaluated using a spectrophotometer, and the pH levels of the solutions were recorded. Results showed that Herculite Ultra XRV had the highest mean contact angle (79.46° ± 6.52), indicating superior hydrophobicity, while Omnichroma had the lowest (64.94° ± 3.08), indicating more hydrophilicity. Significant color changes were observed, especially in black coffee, with ∆E values indicating notable discoloration. The acidic pH of the solutions increased surface roughness and color changes. Statistical analyses confirmed significant increases in surface roughness and color change for all composites, with the nanohybrid resin composite showing the greatest variability. These findings highlight the need for dental restorative materials with enhanced resistance to acidic environments to improve the longevity and esthetics of dental treatments. [ABSTRACT FROM AUTHOR]

Background: Color matching and stability are the essential considerations in restorative dentistry, as they contribute to the longevity and esthetic appeal of the restorations. Composites with nanoparticles and more filler content are anticipated to be more color-stable. Aim: The aim of the study was to assess and contrast the color stability of esthetic restoration materials following exposure to various antioxidant beverages. Materials and Methods: A Class V cavity was prepared on the buccal surface of 40 maxillary premolars. The specimens were divided into two groups: microhybrid (MH) and nanohybrid (NH) composite. The baseline color of each tooth sample was measured and then, the samples were categorized into four subgroups based on the immersion solution (pomegranate juice, beetroot juice, black plum juice, and distilled water) and evaluated on day 1, day 7, day 14, and day 21 using a spectrophotometer-based on CIE L*a*b* color scale. For spectrophotometer analysis, CIE XYZ data were obtained and converted to CIELAB. The samples mean difference in ΔE values before and after being immersed in various beverages. Statistical Analysis: The data were statistically analyzed using an independent t-test and one-way analysis of variance. Results: MH and NH composite materials showed color change after being exposed to the test beverages. Conclusion: MH composite causes more color change than NH composite at all-time intervals. Black plum showed the greatest discoloration in both composites. [ABSTRACT FROM AUTHOR]

It has been developed the detector method of color changing to non-invasive and economical nanofiller composite resin based on optical imaging. The method is chosen due to the easiness of information in images form to be understood. The color changing is represented by the changing of brightness intensity laser which transmitted by samples. The light source uses green pointer laser with 532 nm of wavelength of and webcam sensor which can be obtained in the local market. Fraunhofer diffraction principle is used to utilize set up and test material treatment. By utilizing IC LM 317, it is made a series of regulators so that the laser pointer can be the input voltage from voltage source (AC). The light source of laser pointer is exposed to the test materials for detecting the intensity of transmission. Samples are made as thin as possible in order to transmit light and are given treatment in form of immersion in tea and coffee solution. Immersion is done for 1 week for 4 hours per day. The transmission intensity of samples captured by webcam and processed using the Delphi program. The data collections in form of transmission intensity are in pixel scale. The results indicate that the longer time immersion used affect the transmission intensity of samples decrease. These results can be seen from graph of the relation between transmission intensity with longer time of immersion. This detector can be used to help characterization of color's stability determination on the material which is portable gear. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the effect of whitening toothpastes on the color stability and surface roughness of resin composites stained with coffee and cigarette smoke. Methods: Seventy-two disk-shaped specimens (6 × 2 mm) of suprananohybrid resin composite were randomly divided into two groups and exposed to coffee and cigarette smoke (n = 36). After staining, the samples randomly divided into four groups according to whitening toothpastes and were brushed for 4 min: Opalescence Whitening (OW); Colgate Optic White (COW); Curaprox Black is White (CPX) and, distilled water (control) (n = 9). Color was measured with spectrophotometer at the initial, after staining, and after brushing, and surface roughness was measured with profilometer at the initial and after brushing. A surface morphology analysis was examined using scanning electron microscopy and atomic force microscopy. The obtained data were statistically analyzed. (p < 0.05). Results: Cigarette smoke caused a significantly higher color change than coffee in the resin composite (p < 0.05). Brushing with hydrogen peroxide and silica-containing whitening toothpaste showed significant differences in color change (p < 0.05). The lowest whitening effect was found in activated charcoal-containing toothpaste. While all toothpastes increased the degree of surface roughness of resin composites, the highest roughness was caused by whitening toothpastes containing activated charcoal. (p < 0.05). Conclusions: The color stability and surface properties of resin composites can be affected by brushing them with whitening toothpaste. The utilization of whitening toothpaste containing hydrogen peroxide can be considered a safe method for increasing the whiteness of discolored resin composites. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate how two different polishing techniques affect the color stability, surface roughness, and changes in surface morphology of aged and coffee-stained bulk-fill resin composites. A total of 112 disc-shaped samples were prepared using Omnichroma Flow Bulk (OB), Charisma Bulk Flow One (CB), Estelite Bulk Fill Flow (EB), and Estelite Sigma Quick (control). Samples were divided into two subgroups (n = 16) and aged using thermocycling. A profilometer was used to measure the surface roughness (Ra) and a spectrophotometer was used for color stability (ΔE00). The EB group had the highest Ra values both before aging (disc: 0.23 ± 0.05, twist: 0.42 ± 0.05) and after aging (discs: 0.28 ± 0.04, twist: 0.46 ± 0.05). The OB group had the highest ΔE00 values before and after aging (discs: 3.06 ± 0.54, twist 3.05 ± 0.41) and the highest after coffee-staining (discs: 3.75 ± 0.70, twist: 3.91 ± 0.57). Re-polishing reduced the ΔE00 values in all materials but did not restore all to clinically acceptable levels. According to the results of this study, it can be concluded that the surface roughness and color stability of resin composites are notably influenced by the polishing technique, aging process, and coffee staining. Specimens that were polished using the multi-stage Super-Snap discs consistently exhibited smoother surfaces across all bulk-fill resin composites compared to those polished with the two-stage Diacomp plus Twist. [ABSTRACT FROM AUTHOR]

Resin composites have become the preferred choice for chairside provisional dental restorations. However, these materials may undergo discoloration, changes in surface roughness, and mechanical properties with aging in the oral cavity, compromising the aesthetics, functionality, and success of dental restorations. To investigate the color and mechanical stability of chairside provisional composite resins, this study evaluated the optical, surface, and mechanical properties of four temporary restoration resin materials before and after aging, stimulated by thermal cycling in double-distilled water. Measurements, including CIE LAB color analysis, three-point bending test, nanoindentation, scanning electron microscopy (SEM), and atomic force microscopy (AFM), were conducted (n = 15). Results showed significant differences among the materials in terms of optical, surface, and mechanical properties. Revotek LC (urethane dimethacrylate) demonstrated excellent color stability (ΔE00 = 0.53-Black/0.32-White), while Artificial Teeth Resin (polymethyl methacrylate) exhibited increased mechanical strength with aging (p < 0.05, FS = 68.40 MPa-non aging/87.21 MPa-aging). Structur 2 SC (Bis-acrylic) and Luxatemp automix plus (methyl methacrylate bis-acrylate) demonstrated moderate stability in optical and mechanical properties (Structur 2 SC: ΔE00 = 1.97-Black/1.38-White FS = 63.20 MPa-non aging/50.07 MPa-aging) (Luxatemp automix plus: ΔE00 = 2.49-Black/1.77-White FS = 87.72 MPa-non aging/83.93 MPa-aging). These results provide important practical guidance for clinical practitioners, as well as significant theoretical and experimental bases for the selection of restorative composite resins. [ABSTRACT FROM AUTHOR]

Objective Materials and Methods Results Conclusions The color matching of single‐shade resin composites after in‐office whitening was investigated.Four single‐shade resin composites were used. A total of 35% hydrogen peroxide was used as the whitening agent. The resin composite was placed in a cavity of an artificially discolored bovine tooth. The color differences between the restoration and surrounding enamel before and after whitening were determined based on ΔE*ab, ΔE00, and ΔWID. The color stability, surface roughness (Sa), and surface gloss (GU) of the resin composite alone were also evaluated. Statistical analyses were performed using repeated‐measures analysis of variance with the Tukey–Kramer test.Based on the 50:50% of perceptibility and acceptability thresholds of ΔE*ab and ΔE00, none of the resin composite restorations were clinically acceptable before or after whitening. Regarding ΔWID, although all resin composites showed “acceptable match” in the baseline, they showed “mismatch” after the third session of whitening. Most of the resin composites alone were stable in color against whitening.Although the single‐shade resin composites failed to achieve the expected color matching on discolored teeth either before or after the whitening, the impact of the whitening on the color of the resin composite alone may be negligible. [ABSTRACT FROM AUTHOR]

Objective: To determine the effects of conventional cigarette smoking (CS) and recent heated tobacco products (HTPs) on the surface roughness and color stability of different indirect restorative materials. Materials and methods: One hundred disc-shaped samples were constructed of three different restorative CAD/CAM materials: lithium disilicate glass–ceramic (IPS e.max CAD; Ivoclar Vivadent, Liechtenstein), zirconia (BruxZir® Zirconia, Glidewell, USA) and polyetheretherketone (BioHPP® bredent GmbH, Germany). Of the IPS e.max CAD and the Bruxzir samples, 20 samples were glazed, and 20 samples were polished, while the BioHPP samples were all polished according to the manufacturer's instructions. Fifty samples were subjected to conventional cigarette smoking (LM, Philip Morris International Inc., Egypt) (Groups: IPS e.max CAD_Glazed exposed to CS (LD_G_Cig), IPS e.max CAD_Polished exposed to CS (LD_P_Cig), Bruxzir_Glazed exposed to CS (Zr_G_Cig), Bruxzir _Polished exposed to CS (Zr_P_Cig) and BioHPP exposed to CS (PEEK_Cig) and fifty samples were exposed to heated tobacco product smoking (Heets, Russet selection, Philip Morris International Inc., Italy) (Groups: IPS e.max CAD_Glazed exposed to HTP (LD_G_HTP), IPS e.max CAD_Polished exposed to HTP (LD_P_HTP), Bruxzir_Glazed exposed to HTP (Zr_G_HTP), Bruxzir CAD_Polished exposed to HTP (Zr_P_HTP) and BioHPP exposed to HTP (PEEK_HTP).. Six hundred cigarettes/heets representing 30 days of medium smoking behavior (20 cigarettes/day) were used. Before and after exposure to smoke, the surface roughness of all the samples was measured using JITAI8101 surface roughness tester (Beijing Jitai Tech Detection Device Co., Ltd, China, and the color parameters were assessed using VITA Easyshade Advance 4.01 (VITA shade, VITA made, VITA). The data were analyzed using One-way ANOVA, paired sample t-test and independent sample t-test. The significance level was set at α < 0.05. The surface topography was evaluated by scanning electron microscopy (SEM) and analyzed using energy-dispersive X-ray (EDX) spectroscopy to determine changes in the surface chemical composition. Results: Both types of smoking caused significant increases in the surface roughness of all the samples. There was a significant difference in color change between CS and HTP for all materials with different surface finish (P < 0.01) and zirconia had the greatest effect on color change (P < 0.001). In contrast, polyetheretherketone (PEEK) "BioHPP" had the least effect (P < 0.001). Conclusion: Exposure to different types of smoking induce changes in the surface topography and color of different esthetic restorative materials. Compared with HTP, conventional cigarette smoke has a greater effect on the surface roughness and color stability of esthetic restorative materials. The glazed surfaces showed less change in surface topography than did the polished surfaces. Zirconia showed better color stability when compared to polyetheretherketone (PEEK). [ABSTRACT FROM AUTHOR]

Objectives: To investigate the effect of multiple firings on color, translucency, and biaxial flexure strength of Virgilite-containing (Li0.5Al0.5Si2.5O6) lithium disilicate glass ceramics of varying thickness. Materials and methods: Sixty discs were prepared from Virgilite-containing lithium disilicate blocks. Discs were divided according to thickness (n = 30) into T0.5 (0.5 mm) and T1.0 (1.0 mm). Each thickness was divided according to the number of firing cycles (n = 10); F1 (Control group): 1 firing cycle; F3: 3 firing cycles, and F5: 5 firing cycles. The discs were tested for color change (ΔE00) and translucency (TP00) using a spectrophotometer. Then, all samples were subjected to biaxial flexure strength testing using a universal testing machine. Data were collected and statistically analyzed (α = 0.5). For chemical analysis, six additional T0.5 discs (2 for each firing cycle) were prepared; for each firing cycle one disc was subjected to X-ray diffraction analysis (XRD) and another disc was subjected to Energy dispersive X-ray spectroscopy (EDX) and Scanning electron microscope (SEM). Results: Repeated firing significantly reduced the translucency of F3 and F5 compared to F1 in T0.5 (p < 0.001), while for T1.0 only F5 showed a significant decrease in TP00 (p < 0.001). For ΔE00, a significant increase was recorded with repeated firings (p < 0.05) while a significant decrease resulted in the biaxial flexure strength regardless of thickness. Conclusions: Repeated firings had a negative effect on both the optical and mechanical properties of the Virgilite-containing lithium disilicate glass ceramics. Clinical relevance: Repeated firings should be avoided with Virgilite-containing lithium disilicate ceramics to decrease fracture liability and preserve restoration esthetics. [ABSTRACT FROM AUTHOR]

This study presents an innovative approach to enhancing the shelf life and maintaining the quality of sliced cooked ham through the application of a natural biopreservative derived from lactic fermentation. The biopreservative, at concentrations ranging from 1% to 3.5%, demonstrated substantial efficacy in microbial inhibition, keeping the microbial density low and relatively constant over time (p < 0.05). Remarkably, even at the lower concentration of 1%, the microbial growth rates were significantly reduced, with the treated samples showing notable stability over 24 days at both 7 °C and 25 °C. The microbial count in the treated with biopreservative group was significantly lower (3.19 log cfu/g) compared to the blank (4.59 log cfu/g) and control (5.01 log cfu/g) over 4 days at 7 °C. The shelf life of the ham was 24 days for the blank, 20 days for the control, and 101 days for the treated group at 7 °C. Moreover, colorimetric analysis revealed that the treated samples maintained better color stability, experiencing less variation in the hue angle and chroma, suggesting a protective effect against quality degradation over time. The successful application of the biopreservative aligns with the growing consumer demand for natural food additives and underscores the movement toward sustainable, health-conscious food preservation practices. The findings of this study indicate a promising avenue for the food industry to adopt environmentally friendly alternatives to synthetic additives, which could significantly influence future standards in food processing and preservation. [ABSTRACT FROM AUTHOR]

Aim: This study investigates the interaction of zirconia and polyetheretherketone (PEEK) with indirect composite in fixed dental prostheses. This investigation aimed to assess the shear bond strength (SBS) and color stability of zirconia and PEEK before and after aging, addressing critical concerns in dental restorative applications. Settings and Design: The current in vitro study used 96 samples, 48 of which were divided into two groups, zirconia and PEEK, before and after thermocycling. A dual-axis chewing simulator was used for thermocycling. SBS was measured using a universal testing machine, and color stability was checked using a reflective spectrophotometer. Materials and Methods: Ninety-six samples were categorized into zirconia and PEEK groups, each with subgroups undergoing thermocycling. Samples were prepared using computer-aided design/computer-aided manufacturing milling and veneered with composite resin. Thermocycling involved 10,000 cycles, simulating stress levels equivalent to approximately 1 year of clinical use. SBS was assessed using standardized tests. Stereomicroscopic analysis was performed to evaluate the type of failure. Color stability of the core materials with indirect composite was done using a spectrophotometer before and after aging. Statistical Analysis Used: Statistical analysis included paired t-tests and independent t-tests in SPSS software. Results: The results revealed that SBS values for composite on PEEK decreased from 13.86 ± 0.164 MPa before thermocycling to 13.46 ± 0.185 MPa after thermocycling, with a significant difference (P < 0.005). However, both pre- and postthermocycling values for PEEK were higher than zirconia. The t-test confirmed the lower bond strength of composite to zirconia, with a noteworthy improvement after aging. Stereomicroscopic images revealed adhesive failure for the zirconia group and mixed (adhesive and cohesive) failure for the PEEK group. ΔE values were 3.21 ± 0.127 and 2.93 ± 0.142 for zirconia and PEEK groups, respectively (P < 0.005). Conclusion: Within the limitations of this study, it can be deduced that PEEK is a feasible substitute for zirconia when used in conjunction with indirect composite for the fabrication of dental prostheses. [ABSTRACT FROM AUTHOR]