Antimicrobial Activity, Biocompatibility and Anti-inflammatory Properties of Cetylpyridinium Chloride-based Mouthwash Containing Sodium Fluoride and Xylitol: An In Vitro Study

Abstract

The use of a mouthwash as an adjunct to mechanical plaque removal may be useful to improve oral hygiene. In this study, cetylpyridinium chloride (CPC)-based mouthwashes containing sodium fluoride and xylitol (X-PUR Opti-Rinse 0.05% NaF and X-PUR Opti-Rinse 0.2% NaF) were evaluated for their antimicrobial activity against important oral pathogens associated with dental caries, periodontal disease, and candidiasis. Moreover, their biocompatibility and anti-inflammatory properties were assessed.<br />Materials and Methods: Antimicrobial activity was determined using a disk-diffusion assay, a microplate dilution assay, and the European standard protocols for antiseptics. Microbicidal properties were assessed against both planktonic and biofilm cultures. An oral epithelial cell model was used to evaluate the biocompatibility of mouthwashes and their ability to attenuate cytokine secretion.<br />Results: Using three different antimicrobial assays, the CPC-based mouthwashes were found to be highly active against the tested microorganisms. More specifically, the mouthwashes met the European Standard NF EN 1040 and NF EN 1275 defined as a log10 reduction ≥ 5 (≥ 99.999% killing) for bacteria and log10 reduction ≥ 4 (≥ 99.99% killing) for fungi, respectively. The CPC-based mouthwashes were also bactericidal against biofilms of S. mutans, S. sobrinus, and P. gingivalis. Using an oral epithelial cell model, the CPC-based mouthwashes were found to be less cytotoxic than a chlorhexidine-containing mouthwash used as control. Lastly, the CPC-based mouthwashes decreased the secretion of interleukin-6 and interleukin-8 by lipopolysaccharide-stimulated oral epithelial cells. <br />Conclusion: The CPC-based mouthwashes supplemented with sodium fluoride (0.05% or 0.2%) and xylitol (10%) were highly active against important oral pathogens. Moreover, using an oral epithelial cell model, these mouthwashes were found to be biocompatible and to exhibit anti-inflammatory activity.

Keywords: anti-inflammatory; antimicrobial; biofilm; cetylpyridinium chloride; mouthwash; xylitol.

Fig 1

Log10 reduction (CFU/ml) of S. mutans (panel a), S. sobrinus (panel b), P. gingivalis (panel c), and C. albicans (panel d) following a time contact of 1 min and 5 min in the presence of mouthwashes. *The mouthwash meets the European Standard NF EN 1040 or NF EN 1275 defined as a log10 reduction ≥ 5 (≥ 99.999% killing) for bacteria and log10 reduction ≥ 4 (≥ 99.99% killing) for fungi.

Fig 2

Effects of mouthwashes on viability of oral epithelial cells following a contact time of 1 and 2 min. Cell viability was assessed using an MTT colorimetric assay. Results are expressed as the means ± SD of triplicate assays. *Statistically significant decrease (p < 0.01) compared to control untreated epithelial cells.

Fig 3

Effects of mouthwashes on IL-6 (panel A) and IL-8 (panel B) secretion by oral epithelial cells stimulated with LPS. Cytokine levels in culture medium supernatants were determined by ELISA. Results are expressed as the means ± SD of triplicate assays. ϕStatistically significant increase (p < 0.01) compared to control untreated cells. *Statistically significant decrease (p < 0.01) compared to LPS-stimulated epithelial cells.