Investigation of Water Absorption and Color Change of Indirect Composite Resins

Abstract

Purpose:Since conventional composite resins have some disadvantages such as polymerization shrinkage and secondarycaries formation, indirect restorations are preferred in cases where tooth tissue loss is high. The aim of this study is toexamine the water absorption and color change of indirect composite resins in different beverages.Materials & Methods:In the study, 40 specimens (10×2 mm) were arranged from each composite using three indirect(Signum Composite, Signum Ceramis and Gradia Plus) and one conventional (GrandioSO) composite resin. After thespecimens were polished, they were used for water absorption and color change test. The water absorption test wasperformed through keeping them in water for 7 days as specified in ISO 4049:2009. Samples were kept in coffee, tea anddistilled water for 7 days in order to examine color differences. The water absorption and color change values of thecomposite resins at the end of the 7th day were appraised using one-way analysis of variance (ANOVA) and Tukey’s test(p<0.05).Results:While there was no statistically considerable difference between the water absorption data of the indirect andtraditional composite resin materials we used in the study (p>0.05). When the color changes of resin-containingcomposites in water, coffee and tea were examined, traditional composite resin (GrandioSO) showed statistically lesscolor change than indirect composites in water, coffee and tea (p<0.05).Conclusion:Although indirect composite resins showed similar water absorption with conventional composite, theyshowed more color change than conventional composite. The highest color change in indirect composites was seen incoffee solution. Particle size of the indirect composites do not affect water absorption, but the decrease in particle size ofcomposites shows less color change.