Materials and Methods: Eight flat specimens per group were fabricated for both the test of polishability and the wear test. The following composite materials were included: QuiXX, SonicFill, SureFil SDR Flow, Tetric EvoCeram Bulk Fill, Venus Bulk Fill; control TPH3. For polishability, the surface of the specimen was pre-roughened with 320 grit SiC, and polished under standardized contact pressure of 2N with the diamond-containing one-step polishing system OptraPol Next Generation. After 10s, 20s and 30s polishing time, surface gloss was measured with a glossmeter (Novocurve, 60°, % compared to standard) and mean surface roughness Ra (µm) with an optical sensor (FRT MicroProf). Wear of the composite specimens was tested against IPS Empress antagonists in the two-axis wear simulator Willytec (80N, 0.7mm lateral movement, 1.6Hz, 120,000 cycles). Vertical wear was quantified with the 3D laserscanner Etkon es1. The groups were statistically compared with ANOVA and post hoc Tukey B (p<0.05).
Results: The statistically highest mean surface gloss (72±3%) and lowest surface roughness (0.15±0.02µm) was achieved with Tetric EvoCeram Bulk Fill after 10s of polishing followed by Venus Bulk Fill (45±7%) and TPH3 (48±3%). SonicFill (27±11%), SureFil SDR (21±9%) and QuiXX (10±6%) showed the least surface gloss even after 30s of polishing. QuiXX also exhibited the statistically highest mean total wear (703±118µm) and Venus Bulk Fill (346±43 µm), SureFil SDR (370±54 µm) and Tetric EvoCeram Bulk Fill (381±23 µm) the lowest wear, whereas TPH3 (433±39 µm) and SonicFill (478±39 µm) were in between.
Conclusions: The bulk fill materials differ widely with regard to polishability and wear. Therefore, practitioners are advised to include both parameters in their selection criteria when selecting resins composite for posterior fillings.
Keywords: Composites, Dental materials, Polishability and Wear
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