Objective: This randomized double-blind clinical study evaluated the antimicrobial efficacy of two mouthwashes containing (1) 0.075% cetylpyridinium chloride (CPC) + 0.05% sodium fluoride (NaF) in an alcohol-free base and (2) 0.075% CPC + 0.05% NaF in a 6% alcohol base, versus a negative control mouthwash containing 0.05% NaF in an alcohol-free base on numbers of bacteria in supragingival plaque 12 hours after a single use and 12 hours after 14 days' use.
Methods: Enrolled subjects completed a one-week washout phase prior to providing baseline samples of supragingival plaque that were analyzed for numbers of anaerobic microorganisms. Subjects were randomized to a treatment group and instructed to rinse with 20 mL of the assigned mouthwash for 30 seconds. Post-treatment microbiological analyses were conducted on plaque samples collected 12 hours after the first use of each assigned mouthwash and after completing 14 days of twice-daily use of each assigned mouthwash. Oral examinations were completed by a dentist at each sample collection to assess soft and hard tissue oral health over the course of the study.
Results: The study enrolled 188 adults (mean age 45.78 years; age range 23-69). Subjects rinsing with the CPC-containing mouthwash realized a statistically significant (p < 0.05) reduction in numbers of supragingival anaerobic bacteria at the 12-hour evaluation after a single use. In comparison to the control mouthwash, use of the CPC mouthwash in an alcohol base resulted in a 35.3% reduction in numbers of anaerobic plaque bacteria, while the CPC mouthwash in an alcohol-free base demonstrated a 34.5% reduction. Further, the analysis after twice-daily use for 14 days indicated that the CPC mouthwash in an alcohol base demonstrated a 73.8% reduction in anaerobic plaque bacteria, while the CPC mouthwash in an alcohol-free base demonstrated a 70.9% reduction in anaerobic plaque bacteria versus the control mouthwash.
Conclusion: The CPC mouthwash in an alcohol-free base reduced supragingival plaque bacteria by 34.5% and 70.9% compared to the control mouthwash 12 hours after a single use and after 14 days of use, respectively. In addition, the CPC mouthwash in an alcohol base reduced supragingival bacteria by 35.3% and 73.8% compared to the control mouthwash 12 hours after a single use and after 14 days of use, respectively. There were no statistically significant differences between the CPC-containing mouthwashes at either of the post-treatment time points.