IADR Abstract Archives
In-vitro Biofilm Penetration of Essential Oil-based Alcohol-free Mouth Rinse
Objectives: Examine the penetration of bacterial kill in biofilms treated with either an alcohol-free mouth rinse containing essential oils (EO, LISTERINE® ZERO™), a rinse containing 0.075% cetylpyridinium chloride (CPC), or a combination of CPC and Zinc Lactate (CPC+Z) versus negative control on saliva derived, mixed-species biofilm using established in-vitro methods.
Methods: Confocal Penetration Model(CPM): Saliva-derived mixed species biofilms were grown statically for 48 hours on vertically mounted hydroxyapatite (HAP) discs. Biofilms were treated once for 30 seconds and stained with a live/dead cocktail (Life Technologies). Images were captured using a Leica-SP5 confocal microscope. 3D renderings were generated using Volocity software to visualize penetration. Multi Treatment Biofilm Model (MTBM): Stimulated saliva was dispensed into a 12-channel bio-cassette. A 96-peg polystyrene lid was placed in the bio-cassette with media, and biofilms were formed under continuous flow conditions for 24 hours. Five 30-second treatments were given over 60 hours and biofilms were analyzed for ATP bioluminescence reported as mean log10 relative light units (RLU).
Results: CPM: 3D images qualitatively illustrate the penetration effect of the EO mouth rinse as compared to the CPC and CPC+Z containing mouth rinses. The representative images presented demonstrate the ability of the EO to penetrate to the biofilm-HAP interface; whereas the cationic anti-microbials (CPC, CPC+Z) were less effective in penetration. MTBM: EO mouth rinse showed the greatest level of anti-biofilm efficacy after the 5-treatment regime than all other rinses tested.
Conclusions: These results indicate that in in-vitro biofilm models, the EO mouthrinse, shows the deepest penetration and greatest biofilm kill via live/dead stain over CPC and CPC+Z mouthrinses. Results were similar after one 30-second treatment of a 48-hour-old, saliva-derived biofilm as well as after multiple treatments, further supporting the mechanism of EO to control biofilm growth.
Methods: Confocal Penetration Model(CPM): Saliva-derived mixed species biofilms were grown statically for 48 hours on vertically mounted hydroxyapatite (HAP) discs. Biofilms were treated once for 30 seconds and stained with a live/dead cocktail (Life Technologies). Images were captured using a Leica-SP5 confocal microscope. 3D renderings were generated using Volocity software to visualize penetration. Multi Treatment Biofilm Model (MTBM): Stimulated saliva was dispensed into a 12-channel bio-cassette. A 96-peg polystyrene lid was placed in the bio-cassette with media, and biofilms were formed under continuous flow conditions for 24 hours. Five 30-second treatments were given over 60 hours and biofilms were analyzed for ATP bioluminescence reported as mean log10 relative light units (RLU).
Results: CPM: 3D images qualitatively illustrate the penetration effect of the EO mouth rinse as compared to the CPC and CPC+Z containing mouth rinses. The representative images presented demonstrate the ability of the EO to penetrate to the biofilm-HAP interface; whereas the cationic anti-microbials (CPC, CPC+Z) were less effective in penetration. MTBM: EO mouth rinse showed the greatest level of anti-biofilm efficacy after the 5-treatment regime than all other rinses tested.
Conclusions: These results indicate that in in-vitro biofilm models, the EO mouthrinse, shows the deepest penetration and greatest biofilm kill via live/dead stain over CPC and CPC+Z mouthrinses. Results were similar after one 30-second treatment of a 48-hour-old, saliva-derived biofilm as well as after multiple treatments, further supporting the mechanism of EO to control biofilm growth.