STATEMENT OF PROBLEM The color stainability of recently introduced computer-assisted design/computer-assisted manufacturing (CAD/CAM) hybrid ceramic and resin nanoceramic is unknown. PURPOSE The purpose of this in vitro study was to compare the effect of coffee staining on the color of 3 different CAD/CAM restorative materials and a nanocomposite resin. MATERIAL AND METHODS Specimens from a...

Denture bases may undergo color change over time induced by pigment accumulation within their body; however there is a lack of information regarding the role of yerba mate tea in this process. This work evaluated the effect of five common beverages, including yerba mate tea, on color changes of acrylic denture base resins processed in three different ways. Three different processing techniques ...

purpose:dental shade guides are commonly used for color determination and should be disinfected and sterilized. the purpose of this study was to evaluate the color change of vita 3d master shade tabs after disinfection and sterilization. material and methods:overall, 98 samples (shade tabs) were randomly selected from 14 new, unused vita 3d sets, including the following shades: 2m1, 3l1.5, 3m1,...

The perceived color of an object depends on the chromaticity of its immediate background. But color appearance is also influenced by remote chromaticities. To quantify these influences, the effects of remote color fields on the appearance of a fixated 2 degrees test field were measured using a forced-choice method. Changes in the appearance of the test field were induced by chromaticity changes...

background and aims. the aim of this study was to evaluate the effect of different etching times on enamel color stability after immediate versus delayed exposure to colored artificial saliva (cas). materials and methods. human first premolars were divided into five groups of twenty. a colorimeter was used according to the cie system on the mid-buccal and mid-lingual surfaces to evaluate initia...

abstract:any effects of wood coating with different compounds as nano-zinc, nano-chitosan, chitosan, silicon oil and flaxseed oil on surface properties as; wood color change, surface roughness and wettability were studied in the current research work. for this purpose, sample boards of beech wood were cut into sizes of 2×10×20cm. the specimens were coated with the noticed coatings and tested fo...

The color properties of aging wood samples from historical buildings have been compared with those of recent wood samples that were heat treated at temperatures ranging from 90 to 180°C. The results of kinetic analysis obtained by the time-temperature superposition method showed that the color change during natural aging was mainly due to a slow and mild oxidation process. In other words, heat ...

Given a set S of n points in the plane, each point having one of c colors, the bichromatic all-nearestneighbors problem is the task to find (in the set S) a closest point of different color for each of the n points in S. We consider a dynamic variant of this problem where the points are fixed but can change color. More precisely, we consider restricted problem instances, which allow us to impro...

The objective of this study was to evaluate change in color in experimental titanium-20mass% chromium (Ti-20Cr) alloy in an oral environment. Pure Ti and Ti-6Al-7Nb and Co-29Cr-5Mo alloys, as references to compare change in color, were prepared by casting. The cast specimen was mirror-polished. Each specimen was affixed to a palatal plate and the plate then worn by a volunteer for up to 300 h. ...

Sudden change of every object in a display is typically conspicuous. We find however that in the presence of a secondary task, with a display of moving dots, it can be difficult to detect a sudden change in color of all the dots. A field of 200 dots, half red and half green, half moving rightward and half moving leftward, gave the appearance of two surfaces. When all 200 dots simultaneously swi...