The Gloss Sustainability Of Different Single Shade Composite Resin Materials

The aim of this in vitro study is to determine the effects of different polishing protocols and aging on the gloss values and sustainability of three different single-shade composite resins (Omnichroma, Zenchroma and Charisma Diamond One) and a conventional composite resin (Filtek Z250). A total of 96 composite disc samples (n=24 per group) were prepared. Each group was randomly subdivided into two polishing systems: Sof-Lex disc system and spiral rubber system. All specimens underwent thermocycling for 10,000 cycles (5°C–55°C). Gloss measurements were performed at three different time points: 1. Mylar-finished surfaces(baseline); 2. Polished surfaces (after polishing procedure); 3. After thermocycling using a glossmeter. Statistical analyses were done using Generalized Estimating Equations (GEE), considering material type, polishing system, and time as variables (p<0.05). The highest gloss mean value (115.58 gu) was obtained after polishing in the Zenchroma group which was polished with spiral rubbers. Spiral rubber polishings showed significantly higher gloss values compared to Sof-Lex discs(p=0.007). The gloss values decreased significantly after aging procedure. Both the type of composite resin and the polishing protocol significantly affect initial gloss, however, the gloss values significantly decreased in all groups after aging. Therefore, we suggest that the material type have no significant effect on gloss sustainability over time (p>0.05).