Polishability and Gloss-Retention of Simplified Universal Composite Resins

Objectives: A new universal composite SimpliShade (Kerr Corporation) with simplified shade scheme was recently introduced to provide clinicians with simplified restorative workflow and inventory management. The purpose of this study was to measure and evaluate the polishability and toothbrush gloss retention of SimpliShade along with several commercial universal composites with simplified shade scheme (listed in the table below).
Methods: Specimens for gloss retention and polishability test were light polymerized following the manufacturer’s instructions. The specimens for gloss retention test were first sanded with 240 and then 600 grit sandpapers, and finally polished with Kerr’s Fine and Superfine diamond pastes to achieve the highest Initial Gloss for each composite. Gloss measurement was conducted on the specimen immediately after polishing, then after 7-day aging in 37^oC water, and finally after toothbrush wear testing. Specimens for polishability test were sanded with 240 and 600 grit sandpaper followed by 10-second polishing using the Progloss polisher prior to gloss measurement.
Results: Initial gloss, gloss retention after 7-day aging in 37^oC H2O and 13 hours toothbrush wear, and polishability results for 5 composite resins are summarized in the following Table. Statistical analysis of the data was performed using one-way ANOVA and Tukey’s method for pair-wise comparison to determine significant differences among groups (p<0.05). ANOVA analysis revealed that even though most composite achieved high initial gloss values, SimpliShade yielded the highest gloss retention values after 7-day aging in 37^oC H2O and after toothbrush wear which are statistically higher (p < 0.05) than all other composite resins tested in this study. With just 10s polishing time, Simplishade achieved a very high gloss value (or polishability) that is significantly higher (p < 0.05) than all the other composites with the exception of Filtek Universal.
Conclusions: SimpliShade achieves excellent polishability and highest gloss retention after toothbrush wear as it employs the same nano-filler technology used in Harmonize composite resin.