The aim of the present study was to study if there are interactions and reduced clinical effect between chlorhexidine and fluoride when they are combined in the same mouthrinse.

The investigation assessed the clinical effect of a mouthrinse containing chlorhexidine (CHX) and sodium fluoride (NaF) during a 4-day period of non-brushing and a 6-week period of brushing. Two studies were designed as double-blind, randomized, cross-over clinical trials. In study I, 16 healthy subjects rinsed twice daily for 1 min during 4 days of no tooth brushing with four mouthrinse solutions: 1) 0.12% CHX + 0.2% NaF, 2) 0.2% NaF, 3) 0.12% CHX, and 4) placebo. In study 2, 16 healthy subjects rinsed with the same four solutions twice daily after tooth brushing during a 6-week period. Primary outcomes were plaque formation and gingivitis. Secondary outcomes were fluoride retention and microbiological parameters in plaque and saliva (total bacterial counts and mutans streptococci, lactobacilli and streptococci sanguinis counts). One way analyses of variance with post hoc Student-Newman-Keul´s statistical test was performed for comparisons between mouthrinses. Intragroup changes over time were analyzed with a paired t-test.

Inclusion Criteria:

• Male and female subjects, age 18-35 years
• Good general health
• No signs of periodontitis and caries
• A minimum of 24 teeth with no extensive restorations
• No current or planned dental treatment during the trial periods.

Exclusion Criteria:

• Antibiotic treatment within 1 month prior to the start of the trial
• Current medication with anti-inflammatory drugs
• Use of antiseptic mouthrinses
• Smokers and snuff user
• Use of chewing gums