| dc.description.abstract | Intrudoction: With the progress of adhesive dentistry, composite resin is considered the most widely used restorative material. The polychromatic nature of natural teeth makes composite resins available in a wide shade of colors for the best matchinng with enamel and dentin. Recently, the universal composites have been introduced to simplify color selection and improve color matching. In these copmosites, the “blending effect” improves the color matching ability. This study evaluated the marginal color shifting of three composite resin restorative materials in diffirent cavity depth.
Materials and Methods: 48 human extracted anterior teeth were used for this in-vitro study. The teeth were cleaned with a brush and pumice and kept in distilled water until the test was done. In all teeth, conventional class V cavities (2×2 mm) were prepared on the center of the teeth. The teeth were randomly divided into three groups of 16. Each group of teeth was divided into two subgroups; A and B. Conventional cavities with a depth of 1.5 mm were prepared in subgroup A and conventional cavities with a depth of 3 mm were prepared in subgroup B. After preparing the cavities, the cavitis were restored with Omnichroma composite (Omnichroma, Tokuyama Dental, Tokyo, Japan) in the first group of the teeth, Kalore (Kalore, GC, Japan) in the second group and Essentia universal (Essentia, GC, Japan) in the third group. After polishing the composites, the teeth were kept in distilled water for 48 hours and then the color of the restorations and teeth were evaluated at 4 points by a spectrophotometer device and CIEDE2000 formula. Data were analysed using Two factor ANOVA test.p<0.05 considered as significant.
Results: The type of resin composite material affected the color difference in two points of the composite surface and teeth and two points of the composite surface (ΔE1, ΔE3). (P<0.05) However, cavity depth and the interaction effect of composite*cavity depth had no significant effect on ΔE. Color shifting in the margin of restoration (ΔE2) and the tooth surface (ΔE4) was not affected by the type of composite, cavity depth, and the interaction effect of composite*cavity depth.
Conclusion: The lowest amount of color shifting at the border of the tooth and resin composite was related to Essentia and at a depth of 1.5 mm, However the difference with other composites was not statistically significant. Essentia and Kalore had less color difference in the center of composite and the surface of the tooth and on the surface of the composite, compared to Omnichroma. The cavity depth and the thickness of the composite resin did not have a significant effect on the color shifting between the composite and the tooth. | en_US |
