Effect of finishing and polishing procedures on surface roughness of tooth-colored materials

Objectives: To evaluate the effect of 2 polishing systems on surface roughness of toothcolored restorative materials. Method and Materials: The materials included 3 flowable resins (Admira Flow, Voco; Dyract Flow, Dentsply; Filtek Flow, 3M ESPE) and a microhybrid composite resin (Filtek Z250, 3M ESPE). Eighteen specimens of each material were prepared using a Plexiglas well covered by a Mylar strip (10 mm in diameter and 2 mm in depth). The Ra (baseline) was measured with a Mitutoyo Surftest-402 Surface Roughness Tester (Mitutoyo) with a standard cut-off value of 0.8 mm. Five tracings at different locations on each specimen were made. The specimens were then randomly divided into two finishing and polishing groups (n = 9): (1) Sof-Lex Pop-on disks (3M ESPE), and (2) Astropol and Astrobrush system (Ivoclar Vivadent). After finishing and polishing, surface roughness of the specimens was remeasured. Data were analyzed using 1- and 2-way ANOVA, at P .05. Results: The Mylar strip produced the smoothest surface in all restorative materials, while 2-way ANOVA demonstrated a significant difference for the finishing and polishing procedures (P = .000). The smoothest surface was generated with Sof-Lex Pop-on disks for all the materials tested. In procedure 2 (diamond bur/Astropol and Astrobrush system), Admira Flow group received the highest average surface roughness value, and a significant difference was revealed between Admira Flow and the other resins (P = .001). Conclusion: Sof-Lex Pop-on disks produced a smoother surface than Astropol and Astrobrush silicone polishers for microhybrid and flowable composites. Keywords: flowable resins, surface roughness