This study investigated the alteration of surface roughness of the nanofill composite Filtek Z350 3M/ESPE ® , caused by simulated brushing associated with the use of mouthrinses with or without alcohol. Sixty specimens were prepared and distributed into six groups: distilled water, ethylic alcohol, Listerine ® Vanilla Mint, Plax ® without alcohol, Oral B ® without alcohol and a control group. Each group was submitted to two intercalary 5,000 simulated brushing cycles. At the end of each cycle, the specimens were washed in tap water and immersed for two cycles of six hours equivalent to one year of daily use of the solution for 2 minutes. It was possible to verify significant alteration in surface roughness of the composite influenced by ethylic alcohol. It was not significant for distilled water and the mouthrinses.