Color change of omnichroma composite resin restoration exposed to different stains

Abstract Purpose To investigate the effect of different stains on Omnichroma nano filled composite resin restorations compared to a conventional nano hybrid composite resin restorations. Patients and methods A total of 60 intact human upper premolars with shade A2 were embedded in self-curing acrylic resin (roots only) 2 mm below the cement-enamel junction. A trapezoidal Class V cavity was prepared on the buccal surface of each tooth, a width of 4 mm occlusally and 3 mm gingivally, and 3 mm occluso cervically. The cervical margins were located 2 mm coronal to cementoenamel junction. All cavities were 2 mm in depth. Teeth were randomly divided into two equal groups ( n = 30), group I (Omnichroma composite resin) and group II (Tetric Evoceram composite resin). All specimens were incubated at 37°C, 100% humidity in artificial saliva for 24 h, then subjected to 500 thermo cycles between 5°C and 55°C, 30 s dwell time, and a transfer time of 15 s. The color of specimens and restorations (base line) was recorded by Vita Easy shade V. Each group was randomly subdivided into three sub-groups ( n = 10 specimens) and immersed in artificial saliva, coffee, and tea for 48 h. Color measurements were done again after immersion time. All data was collected, tabulated, and statistical analysis was performed using Statistical Package for Social Science (SPSS version 26). Results In base line evaluation, there was no statistical significant differences for mean values of (ΔE) between both groups and within each group teeth surfaces versus composite restorations, still, there was no significant difference after immersion 48 h in saliva, however, a significant difference was recorded after immersion 48 h in both coffee and tea between both groups regarding composite values, and a statistical significant difference recorded within group II between teeth and restorations. All collected data for tested specimens were analysed to conclude the difference in ΔE of teeth surfaces and composite restorations of both groups between baseline and after 48 h immersion in different solutions, recording a statistical significant difference for teeth surfaces and composites of group I and group II. The difference in (ΔE) between both tested groups regardless the immersion solution was analysed. A significant difference was recorded. Conclusion Omnichroma composite resin matches the shade of tooth for class V restorations. Coffee recorded the highest staining mean values, followed by tea, and lowest mean values recorded by saliva. The claim of manufacturer that Omnichroma has a chameleon effect to obtain the same color of the surrounding tooth surfaces was accepted.