title: Susceptibilities of Enterococcus faecalis biofilms to some antimicrobial medications.
abstract: Enterococcus faecalis has been suggested to be an important etiological agent in endodontic failures. The purpose of this study was to evaluate the effectiveness of chlorhexidine- or antibiotics-based medications in eliminating E. faecalis biofilms. One-day and three-day biofilms of E. faecalis were induced on cellulose nitrate membrane filters. Each biofilm-containing membrane was thoroughly covered with 1 ml of the test medications and incubated for 1 day at 37 degrees C. Treated biofilms were then aseptically transferred to vials containing a neutralizing agent in saline solution and vortexed. Suspensions were 10-fold diluted, seeded onto Mitis salivarius agar plates, and the colony-forming units counted after 48 h of incubation. There were significant differences between the formulations tested. The association of clindamycin with metronidazole significantly reduced the number of cells in 1-day biofilms. However of all medications tested, only 2% chlorhexidine-containing medications were able to thoroughly eliminate most of both 1-day and 3-day E. faecalis biofilms.
authors.affiliation: Department of Preventive and Social Dentistry, Faculty of Dentistry, Federal University of Rio Grande do Norte, Natal, Brazil.
authors.forename: K C
authors.initials: KC
authors.lastname: Lima
authors.forename: L R
authors.initials: LR
authors.lastname: Fava
authors.forename: J F
authors.initials: JF
authors.lastname: Siqueira
mesh_terms: D000704:Analysis of Variance; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D002710:Chlorhexidine / Q000494:pharmacology*; D002981:Clindamycin / Q000494:pharmacology; D015169:Colony Count, Microbial; D004338:Drug Combinations; D013293:Enterococcus faecalis / Q000187:drug effects*; D005782:Gels; D008795:Metronidazole / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D018709:Statistics, Nonparametric
chemical_list: D000900:Anti-Bacterial Agents; D000891:Anti-Infective Agents, Local; D004338:Drug Combinations; D005782:Gels; D008795:Metronidazole; D002981:Clindamycin; D002710:Chlorhexidine