Background and Aim: Nowadays, demand for same–color restorative materials, especially resin composites, is increasing. Access to the smooth surface with minimum level of surface roughness significantly results in more beauty, and the reduction of the accumulation of the plaque, gingival inflammation, and tooth discoloration. the aim of this study was surface roughness of three different composite’s resins following the polish with a two-step technique has been evaluated.
Materials and Methods: In this experimental study, three types of composite; Charisma Classic, Charisma Topaz and Charisma Diamond have been investigated. Every type of the composite includes 40 disc-shape specimens with 5 and 3mm in height were provided. Specimens of each composite type were divided into two categories, tested group and negative control group. The tested groups were polished by twisted and the control groups were not subjected to any kind of polishing process. Then, the overall level of surface roughness in each group was measured. The data were analyzed with independent t test, ANOVA and the Tokay Test.
Results: The mean surface roughness of all three types of composites after polishing by the twisted was significantly lower than the control group

(p <0.001). The mean level of surface roughness in Charisma Classic and Charisma Topaz composites was not significantly different.(P=0.2) the mean surface roughness in Charisma Diamond composite was significantly higher than Charisma Classic and Charisma Topaz composites (p <0.001). The mean of surface roughness was not significantly different between the three control groups (p = 0.24).
Conclusion: Microhybrid composite showed the lowest level of surface roughness after the standard polishing process.
Keywords: composite resins, Dental Polishing, surface roughness