Effectiveness of three oral hygiene regimens on oral malodor reduction: a randomized clinical trial

BACKGROUND: Breath odor is a nuisance problem for many people around the world. Bad breath affects social interactions of people in daily life by causing personal discomfort and emotional stress. There are chemical and mechanical methods for controlling oral malodor. Many studies of various mouth rinse applications and tongue cleaning procedures have been conducted. However, few studies have compared the effect of simultaneous chemical and mechanical procedures on the reduction of volatile sulfur compounds (VSCs) in subjects with oral malodor. The purpose of this study was to assess the effects of different oral hygiene procedures on reduction of VSCs in subjects with oral malodor. METHODS: Thirty male volunteers who matched with study criteria were divided randomly into two groups. Both groups performed tooth brushing, mouth washing with chlorine dioxide, tongue cleaning and combination of those in different sequence for five weeks. Total VSCs of subjects were measured with a Breathtron®, and oral health status was also examined. Quantitative analyses were performed using the Statistical Package for Social Science (SPSS 16.0). RESULTS: There were no significant differences in oral health status between the two groups at the baseline. No significant decrease in oral malodor was detected after one week of tooth brushing. Significant reductions in VSCs were shown by adding mouthwash or tongue cleaning to tooth brushing from the second week to fourth week (P <0.01). The greatest reduction in VSCs was found at the fifth week after the practice of all three oral hygiene regimens. CONCLUSIONS: Tooth brushing alone does not significantly reduce oral malodor. Mouth washing and tongue cleaning significantly reduce oral malodor, but combining tooth brushing, mouth washing and tongue cleaning regimens is most effective for oral malodor reduction. The results of this study could contribute to the formulation of appropriate preventive strategies against oral malodor not only for the general public but also for dental professionals serving as oral malodor-related service providers. TRIAL REGISTRATION: Registration number - ClinicalTrials.gov NCT02113137. Registration date – April 7th, 2014. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13063-015-0549-9) contains supplementary material, which is available to authorized users.