Color stability of denture base acrylic resins in three food colorants

Statement of problem. Three commonly used artificial dyes in food technolog y are erythrosine, tartrazine, and sunset yellow. Purpose. The color stability of 5 commercially available denture base acryl ic resins (QC-20, Meliodent, Trevalon, Trevalon High, and Lucitone) was stu died in vitro. Methods. The specimens were exposed to 3% erythrosine, tartrazine, and suns et yellow solutions at 23 degrees C +/- 1 degrees C. Color changes were det ermined with a computer-controlled spectrophotometer. Five specimens from e ach material were processed, and initial color measurements were made after 1, 3, and 6 months of exposure to the staining solutions. Finally, the col or stability was quantitatively measured again, and color differences (Delt a E) were calculated. Results. For the observations made in 1, 3, and 6 months intervals, the spe cimens that exhibited the least color change were in the sunset yellow solu tion. The greatest color changes observed according to the National Bureau of Standards unit system were Lucitone (2.71) in erythrosine solution, Luci tone (2.54), QC-20 (1.71) in tartrazine solution, and QC-20 (1.66) in sunse t yellow solution. The changes in the other acrylic resins in the 3 solutio ns were slight and at trace level. Conclusions. All materials tested were acceptable from the standpoint of co lor stability for long-term exposure to these food colorants.