Seemann R, Filippi A, Michaelis S, Lauterbach S, John HD, Huismann J. Duration of effect of the mouthwash CB12 for the treatment of intra-oral halitosis: a double-blind, randomised, controlled trial. J Breath Res. 2016;10(3):036002 http://dx.doi.org/10.1088/1752-7155/10/3/036002.
Clinical relevance. Intraoral halitosis (IOH) responds to treatment with mouthwashes containing chlorhexidine, cetyl pyridinium, and zinc. Long-term use of high concentrations of chlorhexidine is associated with adverse effects, which means it is not a good option as a long-term treatment. Researchers are exploring new mouthwash compositions to treat the nearly 30% of patients affected by IOH.
Study summary. Researchers conducted a randomized clinical trial to determine the effects of an active mouthwash containing zinc acetate (0.3%) and a low concentration of chlorhexidine (0.025%). They included 34 adults* with an organoleptic score (OLS) of 2 or greater. OLS is a bad odor measure that ranges from 0 to 5, in which 0 suggests "no odor" and 5 indicates "very strong odor." Researchers assigned participants to receive the active mouthwash and a water mouthwash (placebo) either first or second. On average, the placebo mouthwash did not reduce the OLS 12 hours after the treatment,† but on average the active mouthwash decreased the OLS from 3 to 2.5.‡ A second rinse after the 12-hour interval decreased the OLS by 0.1 in the active mouthwash group and 0.4 in the placebo group. Volatile sulfur compounds (VSC) showed a statistically significant reduction 12 hours after using the active mouthwash compared with using the placebo mouthwash. No serious adverse events were reported, although headaches were reported by 4 participants after using either the active mouthwash or the placebo mouthwash. One patient had a site reaction, and another had dysgeusia after using the active mouthwash.
Strengths and limitations. Researchers excluded participants whose IOH could have been caused by other conditions such as periodontal disease. Although there were no details concerning how patients were randomized and how this was concealed, the use of the crossover design in which all patients receive both treatments reduced the risk of bias associated with these issues. Blinding of the patients, the trained outcome assessors, and the data analysis was optimal. With regards to the applicability of this study, researchers measured breath odor, which is an outcome that is important to patients. Surrogate outcomes, such as the VSC level, have been shown to correlate with breath odor. A potential limitation of this study was the low correlation between the OLS and VSC, which made us less confident of the bad odor measurements. Finally, the fact that the treatment was administered under the researchers' supervision in a highly controlled environment (for example, smoking and diet were controlled the day of the study) and the assessment of the outcomes after only 12 hours may have decreased the applicability of the study to real-life scenarios.
* 50% male; mean age, 44.2 years.
† Mean, 2.8 (standard deviation, 0.7).
‡ Mean difference, –0.5; 95% confidence interval, –0.1 to –0.9.