Surface Roughness and Gloss of Actual Composites as Polished With Different Polishing Systems

This in vitro study evaluated the effect of polishing with different polishing systems on the surface roughness and gloss of commercial composites.

One hundred disk-shaped specimens (10 mm in diameter × 2 mm thick) were made with Filtek P-90, Filtek Z350 XT, Opallis, and Grandio. The specimens were manually finished with #400 sandpaper and polished by a single operator using three multistep systems (Superfix, Diamond Pro, and Sof-lex), one two-step system (Polidores DFL), and one one-step system (Enhance), following the manufacturer's instructions. The average surface roughness (μm) was measured with a surface profilometer (TR 200 Surface Roughness Tester), and gloss was measured using a small-area glossmeter (Novo-Curve, Rhopoint Instrumentation, East Sussex, UK). Data were analyzed by two-way analysis of variance and Tukey's test (α=0.05).

Statistically significant differences in surface roughness were identified by varying the polishing systems (p<0.0001) and by the interaction between polishing system and composite (p<0.0001). Pairwise comparisons revealed higher surface roughness for Grandio when polished with Sof-Lex and Filtek Z250 and Opallis when polished with Enhance. Gloss was influenced by the composites (p<0.0001), the polishing systems (p<0.0001), and the interaction between them (p<0.0001). The one-step system, Enhance, produced the lowest gloss for all composites.

Surface roughness and gloss were affected by composites and polishing systems. The interaction between both also influenced these surface characteristics, meaning that a single polishing system will not behave similarly for all composites. The multistep systems produced higher gloss, while the one-step system produced the highest surface roughness and the lowest gloss of all.