The color stability of resin cements is essential for aesthetic restorations. Aim: To evaluate the influence of shade and aging time on the color stability of two light-cured and two dual-cured resin cements. Methods: The CIE-Lab color parameters (n=6) were measured immediately after sample preparation and at 7, 30 and 90 days of aging in distilled water. The color difference (∆E) was calculate...

> Copper-silica aerogel was synthesized by the sol-gel method and was heated at 400, 500 and 600°C for 3 h in the air. The gained materials were named as sample (a), (b) <span style="font-size: 9pt; colo...

objectives: the aim of this study was to evaluate the effect of six herbal teas on the color stability of two types of nanohybrid and one microhybrid resin composite.  materials and methods: 70 disc-shaped specimens, 210 in total (7*2mm), were fabricated from each of the following materials in metal mould : tetric n ceram, grandio, gradia direct anterior. specimens were stored in distilled wate...

OBJECTIVE In our previous study, glass-fiber-reinforced plastics (GFRPs) made from polycarbonate and glass fibers were prepared for esthetic orthodontic wires using pultrusion. These laboratory GFRP wires are more transparent than the commercially available nickel-titanium wire; however, an investigation of the color stability of GFRP during orthodontic treatment is needed. Accordingly, in the ...

The purpose of this in vitro study was to evaluate the color stability of two brands of porcelain teeth and three brands of acrylic denture teeth. Samples were immersed into three staining drinks as test groups and distilled water as a control. Color measurements of teeth were performed by using a spectrophotometer. Before immersion, the initial color value of each tooth was recorded. Color cha...

OBJECTIVE This study evaluated the influence of light sources and immersion media on the color stability of a nanofilled composite resin. MATERIAL AND METHODS Conventional halogen, high-power-density halogen and high-power-density light-emitting diode (LED) units were used. There were 4 immersion media: coffee, tea, Coke® and artificial saliva. A total of 180 specimens (10 mm x 2 mm) were pre...

the present study attempts to investigate the effect of thermal treatment at 180 °c for 8 hours on chemical changes, quality indexes and oxidative stability of three iranian common virgin olive oils (zard, mari and phishomi). oil samples were taken every 2h of heating treatment and assessed for fatty acid composition, conjugated diene value, carbonyl value, color index and oxidative stability i...

STATEMENT OF THE PROBLEM Evaluation of the color stability of materials used for the fabrication of the base of complete and partial removable dentures provides important information in relation to their clinical service. The color stability of nylon-based polymers as denture bases, compared to that of acrylic resins, has not been extensively evaluated since to date. PURPOSE The aim of the pr...