The SEM analysis demonstrated that three different rough surface disks harbored complex and firmly attached biofilms after gauze scrubbing irrespective of which antiseptic or saline was used.

However, the disks with a turned surface hosted fewer biofilm clusters after scrubbing. This finding is in line with our result showing the better cleansability of gauze soaked in saline on the machined surface implants compared with the rough surface implants. The ultrasonic scaler, air abrasives, and Er:YAG laser have also been well investigated and used for the treatment of peri-implantitis. Schmage et al. revealed the high cleansability of air abrasives and considerable cleansability of ultrasonic scalers and Er:YAG laser on titanium disks contaminated by a biofilm layer of Streptococcus mutans. The cleaning score of the air abrasives was the highest, and two types of ultrasonic scaler with a non-metal tip and the Er:YAG laser showed medium cleaning scores but better cleansability than non-metal curettes or a prophylaxis brush/cup. In the present study, the ultrasonic scaler displayed modest results. The tip used in this study was specially designed for cleansing contaminated implants with complicated macro- and microstructures. As the tip dimension was small in order to cleanse very narrow spaces, such as the valley of micro- or macrothreads, good cleansability was expected to be seen in such areas. This method could remove biofilms from small areas, but not in their entirety and not from the valley of microthreads. Moreover, the overall effect of biofilm removal did not appear impressive. One possible explanation for this result is that a treatment time of 1 min was not sufficient to use this small tip effectively. If more time was given to the ultrasonic scaler group, it might be possible to eliminate more biofilms, especially from microstructured areas of the implant.