Antibacterial Effect of Alcohol-free Oral Rinses on Aspiration Pneumonia-inducing Microorganisms

Abstract

Objectives: This study aimed to evaluate the antimicrobial effects of several commercial alcohol-free oral rinses on aspiration pneumonia‑inducing microorganisms. Methods: The experimental products of three commercial oral rinses (Caregargle, Listerine [coolmint mild], and Garglin [zero]) were selected for the evaluation of antimicrobial effect. Hexamedine and sterile distilled water were used as positive and negative controls, respectively. Four pneumonia‑causing microorganisms and Streptococcus mutans were treated with the experimental oral rinses for one minute, and the live cells were counted as colony-forming units (CFUs). For statistical analysis, one-way ANOVA and Tukey’s hoc test were performed using SPSS version 26.0. Results: Hexamedine and Listerine (coolmint mild) exhibited the highest antibacterial effects against all microorganisms. Caregargle and Garglin (zero) showed comparatively lower antibacterial effects than did Listerine (coolmint mild) and Hexamedine. Conclusions: Hexamedine and Listerine (coolmint mild) displayed significant antimicrobial effects on aspiration pneumonia‑inducing microorganisms. These findings suggest that Hexamedine and Listerine (coolmint mild) products for oral care in hospitalized patients or older adults may be effective in preventing aspiration pneumonia.