Can Reduced-Step Polishers Be as E'ective as Multiple-STep Polishers in Enhancing Sur-ace Smoothness?

Objectives: The aim of this study was to evaluate the effects of various finishing and polishing systems on the final surface roughness of a resin composite. Hypotheses tested were: (I) reduced-step polishing systems are as effective as multiple-step systems on reducing the surface roughness of a resin composite and (2) the number of application steps in an F/P system has no effect on reducing surface roughness. Materials and Methods: Ninety discs of a nano-hybrid resin composite were fabricated and divided into nine groups (n = 10). Except the control, all ofthe specimens were roughened prior to be polished by: Enamel Plus Shiny Venus Supra,One-gloss, Sof-Lex Wheels, Super-Snap, Enhance/PoGo,Clearfil TNist Dia, and rubber cups.The surface roughness was measured and the surfaces were examined under scanning electron microscope. Results were analyzed with analysis of variance and Holm-Sidak's multiple comparisons test (p < Results: Significant differences were found among the surface roughness of all groups (p < 0.05).The smoothest surfaces were obtained under Mylar strips and the results were not differentthan Super-Snap, Enhance/PoGo, and Sof-Lex Spiral Wheels. I he group that showed the roughest surface was the rubber cup group and these results were similar to those ofthe One-gloss, Enamel Plus Shiny, and Venus Supra groups. Conclusions: (I) The number of application steps has no effect on the performance of F/P systems. (2) Reduced-step polishers used after a finisher can be preferable to multiple-step systems when used on nanohybrid resin composites. (3) The effect of F/P systems on surface roughness seems to be material-dependent rather than instrument- or system-dependent.