Abstract
We have used light-cured experimental (Restacril, Nanopacryl, C-foto T, CP-AD1, CP-AD3) composites colouring tests ”in vitro”. The tests were performed on samples of 30 mm diameter and 2 mm thickness, which were immersed in coffee, red wine, and two food colouring agents (red, containing Sunset yellow (E110) and carmoisine (E122), and yellow, containing Sunset Yellow, tartrazine (E102) and Ponceau 4R (E124)). The samples were subsequently removed from the solutions, rinsed with water and dried, and then measured after three days and later after 2 months. On the 2 months-old samples, a bleaching gel was applied (G4, 35%), and the samples were again measured after three hours and after 24 h. The measurements were performed with a UNICAM UV-Vis spectrophotometer. For analyzing the color DE*= f((L*a*b*)) with a spectrophotometer, three discs per composite were prepared. From the reflection spectrum the color coordinates (Da*, Db* DL*) were determined and the color difference. Keywords: dental composites, colour, dental bleaching