Color measurements testing
redness
Color shade assessment using Commission International de L’Eclainge (CIELab) color system (L*, a* and b* values) at baseline before immersion, after one day, and after 14 days by digital spectrometer device Vita Easyshade V (VITA Zahnfabrik, Bad Säckingen, Germany). It is a portable spectrophotometer and a new fifth generation of Easyshade with a handpiece of fiber optic probe assembly for illuminating and receiving the reflected light from the sample. Results appear through a LED screen. The base unit has the calibration block into which the handpiece is seated. The Easyshade handpiece has a 5 mm diameter stainless steel probe [Color difference (ΔEThe L * value represents the lightness of an object where the value of zero equals a perfect black while the value of 100 represents a perfect reflecting diffuser. The a* value is a degree of redness of the color (positive a*; + 80) or its greenness (negative a*; − 80). Finally, the b* value counts for the degree of yellowness (positive b*; + 80) or its blueness (negative b*; − 80). The smaller the ΔE