Cetylpyridinium chloride mouth rinses alleviate experimental gingivitis by inhibiting dental plaque maturation

Oral rinses containing chemotherapeutic agents, such as cetylpyridinium chloride (CPC), can alleviate plaque-induced gingival infections, but how oral microbiota respond to these treatments in human population remains poorly understood. Via a double-blinded, randomised controlled trial of 91 subjects, the impact of CPC-containing oral rinses on supragingival plaque was investigated in experimental gingivitis, where the subjects, after a 21-day period of dental prophylaxis to achieve healthy gingivae, received either CPC rinses or water for 21 days. Within-subject temporal dynamics of plaque microbiota and symptoms of gingivitis were profiled via 16S ribosomal DNA gene pyrosequencing and assessment with the Mazza gingival index. Cetylpyridinium chloride conferred gingival benefits, as progression of gingival inflammation resulting from a lack of dental hygiene was significantly slower in the mouth rinse group than in the water group due to inhibition of 17 gingivitis-enriched bacterial genera. Tracking of plaque α and β diversity revealed that CPC treatment prevents acquisition of new taxa that would otherwise accumulate but maintains the original biodiversity of healthy plaques. Furthermore, CPC rinses reduced the size, local connectivity and microbiota-wide connectivity of the bacterial correlation network, particularly for nodes representing gingivitis-enriched taxa. The findings of this study provide mechanistic insights into the impact of oral rinses on the progression and maturation of dental plaque in the natural human population. Daily use of a mouth rinse can effectively treat the gum disease gingivitis by reducing oral bacterial diversity and plaque formation. Dental plaque is a biofilm formed from multiple bacteria that can cause gingivitis and other infections if it is allowed to mature. Rui Li at Procter & Gamble International Operations in Singapore, and coworkers across China conducted a randomized trial on 91 adults to clarify the response of oral bacteria to treatment with cetylpyridinium chloride-based (CPC) mouth rinse. After intensive oral hygiene treatment for 21 days, the participants were split into a control group (given only water) and a CPC rinse group. Both groups followed a daily rinsing routine for three weeks. The team found the CPC rinse inhibited 17 gingivitisassociated bacteria, and significantly reduced plaque formation by disrupting bacterial interactions.