Surface Roughness and Gloss of Composite-resins Using Different Polishing Systems

Objectives: The purpose of this in vitro study was to determine the minimum polishing time to obtain the maximum gloss and the lowest surface roughness and to evaluate the gloss and surface roughness on the surface of five resin composites polished with three polishing systems.
Methods: The specimens (W = 5 mm, L = 12 mm, 2-mm thick) were prepared and cured with Filtek Z250 (Z2), Filtek Z350XT (Z3), Metafil CX (ME), Venus Diamond (VE), and Ceram_X (CE). Five specimens of each resin composite were randomly assigned to be polished with one of three polishing systems including Soflex-XT (SX), Enhance Multi (EM), and Soflex-Diamond (SD) for a minimum interval of 20 s. The gloss (GU) and Ra on the surface were measured with a glossmeter and a surface profilometer at every polishing step. The results were compared with ANOVA at each time point (alpha = .05).
Results: GU of specimens polished with EM and SD were higher than those polished with SX. When polished with SX, CE showed lower GU, while Z2, Z3, and ME showed higher GU. ME and CE showed lower GU when polished with EM and SD. All composites showed higher GU with EM and SD than with SX. The polishing time required to obtain Ra < .02 micrometer for all composites was SX < SD < EM.
Conclusions: The maximum GU achieved during polishing was different with the types of composites and the polishing systems. Ra for all specimens reached below .02 before completing all polishing procedures regardless of polishing systems.