Farah RI. Restor Dent Endod. 2018 Nov;44:e3. https://doi.org/10.5395/rde.2019.44.e3

Spectrophotometric evaluation of color changes of Bleachshade resin-based composites after staining and bleaching. Aim: The aim of this study was to evaluate the color stability of two commercially available bleach-shade resin composites (RC) after exposure to 3 storage solutions and the effect of 3 bleaching agents on the color stability and stain removal from stained RC. Materials and methods: Two bleach-shade RC were evaluated in this study, including a nanofilled RC, Filtek^TM Z350 XT (FZ), and a nanohybrid RC, Tetric® N-Ceram (TC), in the extra-white body (shade) (XWB) and L shades, respectively. Twenty-seven disk-shaped specimens, each measuring 12 mm in diameter and 2 mm in thickness, were prepared for each RC, with a total of 54 specimens. Specimens were randomly allocated into 3 groups of 9 specimens each and immersed in 3 storage solutions (distilled water, tea and coffee) for 7 days period. The 9 specimens in each staining group were further divided into 3 subgroups. Specimens in each subgroup (n = 3) were bleached using one of the bleaching agents (10 and 16% Zoom NiteWhite amorphous calcium phosphate (ACP), and Zoom 2 chairside with light activation) for 5 days period. The specimen colors were measured with spectrophotometer. The measurements were performed on each sample three times at baseline, after staining, and after bleaching. Color was expressed using the commission international de I'Eclairage (CIE) L*a*b* color space. The color differences (ÄE) between the three measurements were calculated and the results were statistically analyzed using Two-way and Three-way analysis of variance (ANOVA) and Tukey's posthoc tests. Level of significance was set at p < 0.05. Results: Tetric® N-ceram materials demonstrated significantly less color change than the FZ and the color change, which was greater after storage in coffee compared to tea, was statistically significant. The bleaching agents significantly influence the color changes of composite specimens. All groups showed (ÄE) values below 3.3 after bleaching, except for ‘Zoom 2 chairside’ with light activation groups, which is shown clinically unacceptable lighter shade (ÄE >3.3). Conclusion: Bleach-shade composites showed significant discoloration (ÄE > 3.3) after being immersed into coffee and tea solutions. Nanofilled composites discolored more than nanohybrid composites, and carbamide peroxide-based bleaching agents were effective in reducing the discoloration to a clinically acceptable value (ÄE > 3.3). How to cite this article: Farah RI, Elwi H. Spectrophotometric Evaluation of Color Changes of Bleach-shade Resin-based Composites after Staining and Bleaching. J Contemp Dent Pract 2014;15(5):587-594.

Background: This study sought to determine the prevalence of carotid artery calcifications (CACs) and pulp stones detected on panoramic radiographs (PRs) and ascertain their correlation. Methods: A total of 2013 digital PRs were retrospectively retrieved and thoroughly examined to determine the prevalence of CACs and pulp stones, their correlation with patient age and gender, and the relationship between the presence of pulps stones and radiographically detectable CACs. Results: The prevalence of CACs on PRs was 2.0%; the prevalence of pulp stones was 4.6%. There was no statistical relationship between pulp stones and CACs (p = 0.714). Older patients exhibited a significantly higher prevalence of CACs than younger patients (p < 0.001); pulp stones were statistically more prevalent in younger patients than older patients (p = 0.001). There were no significant differences between male and females in terms of the prevalence of either CACs or pulp stones (p = 0.087 and p = 0.278, respectively). Conclusions: Dentists should be trained to detect CACs on PRs belonging to patients older than 40 to exclude the presence of CACs. Moreover, pulp stones do not function as a diagnostic marker for CACs.

Electrolyzed water is a safe, broad-spectrum bactericidal and viricidal agent, which can be used as a potent and effective alternative disinfectant in case of supply shortages. This report describes the on-site production of slightly acidic electrolyzed water (EW) from diluted salt solution and vinegar at a dental office using a portable EW generator unit. Such measures can ensure the safe continuity of important dental service provision for our patients during the coronavirus disease 2019 (CoVID-19) pandemic.