In vitro Resistance Testing of Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia to Triclosan.

AIM: To determine the sensitivity of Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia to triclosan, and determine if these bacteria develop resistance to triclosan upon prolonged exposure.

MATERIALS AND

METHODS

Susceptibility to triclosan was tested against three periodontal pathogens P. gingivalis, P. intermedia, and T. forsythia. Escherichia coli strains sensitive and resistant to triclosan were used as biological controls to confirm the efficacy of triclosan in the assays. Agar plates were prepared locally with vitamin K and hemin-supplemented medium.

RESULTS

Porphyromonas gingivalis and P. intermedia did not grow on plates containing ≥ 2 μg/ml triclosan, while T. forsythia did not grow on ≥ 1.66 μg/ml. Colonies of P. intermedia resistant to triclosan developed after prolonged incubation at 2 μg/ml, but this resistance disappeared during subculture in the absence of triclosan.

CONCLUSION

No significant resistance to triclosan was detected for these species.

CLINICAL SIGNIFICANCE: Dental products containing triclosan can be beneficial in controlling periodontal disease.