Reducing Oral Malodor with a Fluoride and Zinc Containing Mouthrinse

Objective: The purpose of this study was to determine the degree and duration of effectiveness of a fluoride and zinc containing mouthrinse, Listerine® Total Care (LTC), in reducing and controlling human intrinsic oral malodor, for up to four hours, following a single-rinse, using hedonic methodology, compared to a positive control, Advanced Listerine® (AL), and a 5% Hydroalcohol (negative control) rinse. Method: This was an observer-blind, single-center, one-day parallel group, controlled clinical trial. 129 qualified subjects were asked to refrain from oral hygiene procedures, eating and drinking on the morning of the oral odor evaluations. Breath odor was evaluated by five expert judges using a 9-point hedonic scale. Those subjects with hedonic scores between 6.0 and 8.4 and no individual rating ≤ 4.0 were randomly assigned to one of three treatment groups. Subjects rinsed once for 30s with 20mL of one of three products: LTC, AL, or negative control. Malodor assessments were conducted at baseline and post-treatment evaluations (30, 60, 90, 120, 180 and 240 min) to determine mean hedonic ratings for each time point. Between-treatment comparisons of mean hedonic ratings were based on analysis of covariance (ANCOVA) model. Results: The mean hedonic odor ratings for LTC mouthrinse and the positive control (AL) were statistically significantly better than the negative control at all time points (p≤0.002). Conclusions: In a single use, one-day oral malodor hedonic model, Listerine® Total Care mouthrinse was more efficacious in reducing oral malodor in hedonic scores than the negative control through 4 hours.