Long-term management of plaque and gingivitis using an alcohol-free essential oil containing mouthrinse: a 6-month randomized clinical trial.

Purpose: This 6-month, examiner-blind, single center, randomized, parallel group, controlled clinical trial compared the antiplaque/antigingivitis effects of an alcohol-free EO mouthrinse (LISTERINE Zero) to a negative control (5% flavored, colored hydroalcohol) and to an alcohol-free CPC-containing mouthrinse (Colgate Plax).

Methods: 337 gingivitis subjects were clinically examined to determine Modified Gingival Index (MGI) and Plaque Index (PI) at baseline, 3 and 6 months. The primary efficacy variables were mean MGI and mean PI at 6 months (statistically analyzed by ANCOVA). After professional dental prophylaxis, subjects were randomly assigned to 6-month twice daily unsupervised use of alcohol-free EO, alcohol-free CPC or a negative control rinse, in conjunction with normal brushing and flossing. Safety was monitored throughout the study.

Results: 311 subjects completed the study. After 6 months of use, EO significantly reduced plaque (31.6%) and gingivitis (24.0%) compared to negative control. At 6 months, CPC also significantly reduced plaque (6.4%) and gingivitis (4.4%) compared to negative control. EO provided a 26.9% decrease in plaque and a 20.5% decrease in gingivitis compared to CPC (P < 0.001). All rinses were well tolerated. The alcohol-free EO mouthrinse demonstrated superior efficacy in reducing plaque and gingivitis over 6 months compared to both negative control and alcohol-free CPC mouthrinse.