Halitosis is often caused by a change in the oral biofilm, primarily located on the surface of the tongue. A suction tongue cleaner enables professional cleaning of the tongue. The aim of this study was to investigate the acceptance and efficiency of a suction tongue-cleaning device in adults in comparison to a conventional manual tongue cleaner in an office (professional) setting. Both were tested simultaneously on 100 individuals with a split-mouth (i. e. half-tongue) design, between the ages of 19 to 31, at the University Center for Dental Medicine Basel UZB. To evaluate the efficiency of the cleaning, photos were taken before and after the cleaning and later assessed by using a modified coating tongue index by Winkel (WTCI). Both cleaning devices significantly reduced the coating on the tongue (p < 0.001). In 58 cases, the side cleaned with the suction tongue cleaner resulted to be cleaner in comparison to the side which was cleaned manually. There were no significant differences in acceptance on a visual analogue scale (VAS, 0-10 cm) between the devices (p = 0.259). However, 53 subjects favored the manual method in comparison to 36 who favored the suction device. The remaining 11 did not convey any preference for either. Both devices triggered an equally frequent gag stimulus. With 95%, the majority of the patients who had this treatment would undergo it a second time. In conclusion, both cleaning devices resulted in a significant reduction of tongue coating, and the usage in general can be highly recommended. While it does not matter which one is used, the suction tongue-cleaning device offers a good alternative to manual tongue-cleaning devices in dental clinics and can be considered a viable adjunct for in-office use.