A COMPARISON OF THE COLOR STABILITY OF THREE DIFFERENT BASE MATERIALS IN THE DIFFERENT SOLUTIONS

Purpose: the drawback of the acrylic materials that are used for making removable dentures is the change in esthetic and mechanical properties over time. color stability of acrylic materials is an important criterion that should be considered from esthetical standing point. the color change of denture materials presents important information on the long term availability. the aim of this study was to determine the color change of different denture base materials stored in different solutions by the time. material and methods. 3 different denture base materials; conventional compression molded pmma (meliodent), injection molded pmma (sr-ivocap) and injection molded poliamid denture base material (deflex®), were kept in 5 different solution (tea, distilled water, coffee, coke and wine) for 30 days (n=8). color stability was measured with spectrophotometer at 4 different time points (time 0 and on 1st, 7th and 30th days). measurements on each specimen were repeated 3 times on 3 different areas. the color change (δe) was used for statistical analysis. tea was prepared using one tea bag per 150 ml hot water. instant coffee was prepared by mixing 2 grams coffee in 150 ml hot water. 150 ml of coke and wine were poured directly from their bottles. solutions were renewed every 24 h. results: statistically significant differences were found between materials, solutions and time intervals. the effect of different solutions on color change (δe) of denture materials was significant (p<0.001). the specimens that were kept in tea were stained significantly more compared to the other solutions. there was no significant difference in discoloration effect of wine (p=0.99), coke (p=0.47) and coffee (p=0.54) compared with distilled water. while the color change on polyamide specimens was the highest, specimens in ivocap group were more resistant to color change compared to the other groups (p<0.0001). conclusion: when kept in different solutions taken intraorally, polyamide denture base material was more stained than the polymethylmetacrylate base materials. the longer the specimens were kept in solutions, the higher was the color change. the color change of denture base materials was highest in tea.