Background To evaluate the efficacy of two alcohol-free antimicrobial mouthrinses in reducing plaque and gingivitis compared to an alcohol-containing rinse and toothbrushing alone.

Methods 160 healthy volunteers were enrolled in the parallel-design examiner-blind study. After screening and stratification by sex and papillary bleeding index (PBI), participants were randomly and equally assigned to four groups: (1) toothbrushing + rinsing (0.06% CHX + 0.025% NaF, alcohol-containing rinse, Corsodyl® Daily Defence Mouthwash; positive control); (2) toothbrushing + rinsing (0.06% CHX + 0.025% NaF, alcohol-free experimental rinse); (3) toothbrushing + rinsing (0.06% CHX + 0.03% CPC + 0.025% NaF, alcohol-free experimental rinse); (4) toothbrushing alone (negative control). At baseline, Quigley-Hein plaque index (QHI), the modified proximal plaque index (MPPI), and PBI were recorded. All subjects were advised to brush their teeth as usual during the eight weeks study period. Additionally, groups 1-3 were instructed to rinse twice daily (30 sec. each). All participants used Dr. Best multi aktiv toothpaste and Dr. Best plus toothbrush (medium stiffness). Eight weeks after baseline, indices were recorded again. Anova with Bonferroni adjustment was used for statistical analysis.

Inclusion Criteria:

• participants between 18 and 65 years
• no severe periodontitis
• informed consent

Exclusion Criteria:

• handicapped participants
• allergies against mouth rinses