Gloss Retention of Direct Composites and Corresponding CAD Composite Blocks

Objectives: The aim of the study is to compare gloss retention of 4 different composites and compare the results with the ones obtained with CAD blocks made out of the corresponding direct composite resins.

Methods: Four direct composites and corresponding CAD composite blocks were tested: Filtek Supreme XTE A2 Body and Lava Ultimate A2 14LT (3M, St. Paul, MN, USA), Tetric EvoCeram A2 and Tetric CAD A2 (Ivoclar-Vivadent, Schaan, Liechtenstein), GrandioSO A2 and GrandioSO CAD A2 (VoCo, Cuxhaven, Germany), G-aenial Universal Injectable A2 and Cerasmart 270 A2 LT (GC, Tokyo, Japan). A total of 12 disc-shaped specimens were made for each tested composite and for each test. All specimens were polished by means of Soflex discs (3M) up to the finest grit. Three different tests were performed: Brushing, exposition to acidic fluoride gel (Elmex gelée, Gaba, Therwil, Switzerland) and exposition to alcoholic solution. Gloss values were obtained by means of a glossmeter (Novo-Curve, Rhopoint Instrumentation Ltd., Bexhill on Sea, UK) at T0 min, T15 min, T30 min and T60 min intervals and ΔGU were then calculated.

Results: In the brushing test, ΔGU ranged from to 22.0 (Filtek Supreme) to 69.9 (GrandioSO CAD). In alcoholic solution exposition, ΔGU ranged from -6.5 (Lava Ultimate) to 5.6 (GrandioSO). In acidic fluoride gel exposition, ΔGU ranged from 48.8 (GrandioSO CAD) to 25.8 (Tetric EvoCeram). Statistical analysis by means of Anova and Tukey post hoc test revealed significant differences between groups.
Conclusions: Gloss retention is dependent on material composition and fabrication mode.