Previous studies have shown CIO2 to have proven oxidizing and microbiological efficacies, but until now its effectiveness in oral care applications has only been measured using organoleptic means.
In view of this the team of researchers from a number of institutions in Japan and headed up by Kayoko Shinada, set out to assess inhibitory effects of CIO2 on volatile sulfur compounds using gas chromatography as a means of determining its effect in mouthwash formulations on morning oral malodor.
Two group, two weeks and cross-over
The method for the research used a randomized, double blind, crossover, placebo-controlled two week clinical trial and was carried out among 15 male volunteers who were divided in two groups.
The first group was initally instructed to rinse with a mouthwash that had been formulated with CIO2, and the second group were told to use a placebo mouthwash that had not been formulated with the substance.
Each group used the mouthwash for one week (phase 1), then in the second week (phase 2), each group swapped the mouthwash they used as a means of providing a more accurate comparison of the results
Malodor assessed every 30 minutes
In both groups and in both of the test phases, malodor was assessed on a daily basis; before rinsing and every 30 minutes up to 4 hours using organoleptic measurements (OM).
The measurements determined the presence of hydrogen sulfide (H2S), methyl mercaptan (CH3SH) and dimethyl sulfide ((CH3)2S), the main VSCs of human oral malodor, and were evaluated with GC using chromatography.
The results found that, although the baseline oral condition did not differ significantly in either of the two groups, the OM readings for the mouthwash containing CIO2 did show a significant improvement in morning bad breath, reducing concentrations of all the substances that were tested for.
Likewise, the results also showed that the CIO2 mouthwash helped keep all of these substances and the resulting malodor under control for at least four hours after the mouthwash was used, significantly better results than the placebo mouthwash.