Title: Metabolic and Antibacterial Effects of a Dual-phase Mouthwash
Grace Haddad, The University of Manchester
Ruth Ledder, University of Manchester
Jodie Penney, University of Manchester
Kara Buzza, The University of Manchester
Prem Sreenivasan, Colgate-Palmolive, Co.
Andrew McBain (Presenter)
University of Manchester
Objectives: Mouthwashes can benefit oral health through the control of bacterial growth and by reducing harmful bacterial metabolic processes that are responsible for common oral conditions. This study investigated the antibacterial effects of a dual-phase mouthwash containing 0.075% (v/v) cetylpyridinium chloride [test] in comparison to a fluoride rinse [control].
Methods: The antimicrobial effects of each mouthwash immediately after treating Actinomyces viscosus were evaluated using a cell viability indicator dye that also determined minimum inhibitory concentrations (MIC) against Streptococcus mutans. The effects of these treatments to inhibit microbial acid production were evaluated using the minimum acid neutralizing concentration (MNC) assay and a novel sugar analogue metabolism assay examined the minimum sugar metabolism inhibitory concentrations (MiSMIC) for S. mutans. An additional evaluation determined the effects of the test in comparison to a control rinse on oral samples collected from ten adult subjects (age range 26-45 years; comprising six females and four males) using an ex-vivo assay.
Results: The test mouthwash rapidly inactivated oral bacteria (viability values were significantly lower following exposure to test (0.007) compared to control (0.703). The MIC was 0.093% for test and >50% for control and the MNC was <0.087% for test and 25% for control. The MiSMIC was <0.024% (v/v) for the test rinse was and 0.694% (v/v) for control mouthwash. Results from the ex-vivo assay demonstrate that treatment of oral samples with the test mouthwash led to a greater than 99.9% reduction in bacteria than after treatment with the control (p<0.05).
Conclusions: Results from this investigation indicate the significantly greater inhibition of bacterial growth, microbial acid production or sugar metabolism in a range of tests and on oral samples collected from adult volunteers by the dual phase mouthwash formulated with cetylpyridinium chloride.