Evaluation of Two Novel Alcohol-Free Oral Rinses Containing a Biguanide and Botanicals against Ventilator-Associated Pneumonia Pathogens Using an in vitro Biofilm Model

The objective of this study was to evaluate the efficacy of two novel alcohol-free oral rinses: polyhexamethylene biguanide botanical oral rinse (PBOR) and chlorhexidine gluconate botanical oral rinse (CBOR), against common ventilator-associated pneumonia (VAP) pathogens using in vitro methods and compare their antimicrobial activity to commercially available oral care products viz. Listerine, Scope and Gum. PBOR and CBOR were highly effective in rapid-kill (15s exposure) tests against VAP pathogens. PBOR, CBOR and Gum displayed equivalent prophylactic antimicrobial activity. In vitro artificial-teeth model showed that PBOR and CBOR were significantly effective against S. aureus and P. aeruginosa compared to others (P <0.05). SEM images revealed that PBOR and CBOR show efficacy in inhibiting biofilm forming P. aeruginosa on artificialteeth surfaces. In conclusion, our in vitro studies demonstrated that PBOR and CBOR are more effective against VAP pathogens compared to commercial mouth rinses and they can also inhibit biofilm formation.