Objective: To compare and evaluate the effect of 0.2% chlorhexidine gluconate and commercially available herbal mouthrinse in reducing aerosolized bacteria when used as a preprocedural mouth rinse. Materials and methods: A total of 45 patients were selected and randomly divided into three equal groups. As the preprocedural rinse, patients belonging to group I, group II and group III rinsed with distilled water, 0.2% chlorhexidine mouthwash (Clohex®) and herbal mouthwash (Hiora®), respectively, for 60 seconds. Aerosols produced during the oral prophylaxis procedure were collected on blood agar plates by exposing the plates to the patient's and dentist's chest area, and the plates were incubated at 37°C under aerobic conditions for 48 h. The number of colony forming units (CFU) in the aerosol were counted and statistically analyzed. Results: At both the locations the mean CFU were highest in Group I followed by Group III and Group II. The 0.2% chlorhexidine gluconate mouthwash was superior in significantly reducing the aerosolized bacteria during scaling, followed by herbal mouthrinse and distilled water (p≤0.0001). Conclusions: The results of the present study clearly indicate that preprocedural rinsing with 0.2% chlorhexidine gluconate was significantly more effective than herbal mouthrinse in reducing the aerosolized bacteria during ultrasonic scaling. Therefore a preprocedural rinse can significantly reduce the risk for crosscontamination.