Discoloration of Resin Composites Induced by Coffee and Tomato Sauce and Subjected to Surface Polishing: An In Vitro Study.

BACKGROUND The purpose of this study is to evaluate and compare color stability of 3 resin based restorative materials when immersed into staining media at 0, 3, 30, 45, 60, and 75 days, and to assess the efficacy of surface polishing in reducing possible discoloration. MATERIAL AND METHODS Ninety composite discs were prepared in a custom-made mold (5 mm diameter and 2 mm thick) from 3 different light cured composites (Filtek™ Z250, Harmonize™, and G-aenial). Color differences of all specimens were measured by a spectrophotometer according to the CIE L*a*b* system. After baseline color measurements, 30 discs from each composite group were randomly divided into 3 subgroups of 10 specimens each. Subgroups (n=10) were immersed for 75 days into different staining solutions: coffee, tomato sauce, and distilled water (control). Solutions were changed every week and color measurements were repeated every 15 days. At day 75, color measurements of the specimens were performed before and after surface polishing with aluminum oxide discs. The experimental data were statistically evaluated using repeated measures one-way ANOVA test followed by Tukey's multiple pairwise comparison with a significance level of 5%. RESULTS Of the 3 composites, G-aenial reported the highest color change deviation when immersed into coffee (ΔE=8.674), and tomato sauce (ΔE=7.737) at day 75, followed by Harmonize that also exhibited a significant difference for coffee (ΔE=4.7) and tomato sauce (ΔE=3.8) when compared to distilled water. While Filtek™ Z250 did not show any significant difference between the 3 storage solutions (P>0.05). Only G-aenial had significant color change (P<0.05) after polishing with aluminum oxide discs for all tested samples, whereas Filtek™ Z250 and Harmonize presented no significant difference after surface polishing (P>0.05). CONCLUSIONS Under the tested experimental conditions, Filtek™ Z250, among the 3 resin-based composites, exhibited the highest color stability when subjected to coffee and tomato sauce as well. Whereas, G-aenial presented the highest color deviation when immersed in both staining media. Surface polishing effectively reduced coffee and tomato sauce discolorations for G-aenial's specimens and had no significant effect regarding Filtek™ Z250 and Harmonize.

Assessing Dental Light-curing Units' Output Using Radiometers: A Narrative Review.

INTRODUCTION: This review aimed to describe dental radiometers and discuss their effectiveness compared to other light-testing devices. MATERIALS AND METHODS: The search for light-curing units (LCUs), radiometers, and other light-measuring tools available on the market was accomplished on data found on PubMed, Wikipedia, and Google. RESULTS: LCUs are prone to deterioration due to several reasons such as the light's limited life span, the worsening of the LCU's filters, light guide, and light tip end; consequently, decreased photopolymerization and insufficient resin conversion may occur. A regular light output assessment is highly recommended in dental daily practice as well as before any new LCU purchase to make sure the light features meet the factory specifications delivered by the manufacturer and they remained stable through time. DISCUSSION: Irradiance values reported by radiometers do not match accurately with those delivered by laboratory power meters. Therefore, dental practitioners as well as dental students are advised to control regularly every LCU by using the same handheld radiometer.

Four-Year Follow-up of Increased Vertical Dimension of Occlusion using Resin Composites.

The objectives of this case report were to treat a severe loss of the vertical dimension of occlusion with indirect composite and to evaluate the durability of the restorations. A 55-year-old male complains from severe wear of teeth, leading to a change in normal occlusal plane. Two major treatment modalities were proposed to this patient; a conventional invasive crown placement with root canal treatments or a minimally invasive approach relying on adhesion. The latter was adopted and used to treat this patient. This paper describes a step-by-step approach of the different treatment phases starting with teeth preparation, then provisional prostheses, and ending with the placement of indirect anterior veneers and posterior onlays, all made with laboratory resin composite. Satisfactory clinical results were observed over the 4-year follow-up, with minimum failures limited to one partial fracture of inlay treated with direct adhesive repair.