Susceptibility of oral bacteria to phenoxyethanol and phenoxyethanol/chlorhexidine combinations

A total of 57 bacterial strains (26 different species) which may be isolated from subgingival plaque were tested for their in vitro susceptibility to phenoxycthanol, a commonly-used antiseptic and preservative. Ninety-five percent of the strains, including those associated with chronic inflammatory periodontal disease, were susceptible to concentrations of phenoxyethanol used topically (2% w/v). Phenoxyethanol at a concentration of 1% (w/v) was also found that to have a rapid bactericidal effect achieving a 99.9% kill in 5 minutes or less for species such as Bacterodides gingivalis, Fusobacterium nucleatum, Eikenella corrodens, and Wolinella recta. Addition of chlorhexidine to phenoxyethanol resulted in a mixture with increased antibacterial activity. For most bacterial strains, the presence of chlorhexidine resulted in at least a four-fold decrease in the concentration of pheoxyethanol required for inhibition of growth. These results imply that phenoxyethanol may be useful in the treatment of chronic inflammatory periodontal disease either by itself or in combination with chlorhexidine.