title: Single species biofilm-forming ability of root canal isolates on gutta-percha points.
abstract: The participation of bacterial biofilms in the over-filled gutta-percha points associated with refractory periapical periodontitis has recently been reported. This study investigated the initial biofilm-forming ability of root canal isolates (Enterococcus faecalis, Streptococcus sanguis, Strep. intermedius, Strep. pyogenes, Staphylococcus aureus, Fusobacterium nucleatum, Propionibacterium acnes, Porphyromonas gingivalis and Prevotella intermedia) on gutta-percha points in vitro. Each bacterial strain was suspended in 100% cell culture medium or in culture medium containing 4.5, 45 or 90% (vol/vol) serum. The bacterial suspensions were then co-incubated anaerobically with gutta-percha points for 7 d. The gutta-percha points were processed for scanning electron microscopic observation and examined for biofilm presence and thickness. E. faecalis, Strep. sanguis, Strep. intermedius, Strep. pyogenes and Staph. aureus biofilms were generated on the surfaces of the specimens incubated in culture medium supplemented with 45 or 90% (vol/vol) serum. The E. faecalis and Strep. sanguis biofilms were significantly thicker than those of Strep. intermedius, Strep. pyogenes and Staph. aureus. No biofilms were detected on the specimens incubated with F. nucleatum, Prop. acnes, Porph. gingivalis and Prev. intermedia. These findings suggest that Gram-positive facultative anaerobes have the ability to colonize and form extracellular matrices on gutta-percha points, while serum plays a crucial role in biofilm formation.
authors.affiliation: Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Osaka 565-0871, Japan. noiri@dent.osaka-u.ac.jp
authors.forename: Naoki
authors.initials: N
authors.lastname: Takemura
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Noiri
authors.forename: Atsushi
authors.initials: A
authors.lastname: Ehara
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawahara
authors.forename: Nobuo
authors.initials: N
authors.lastname: Noguchi
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Ebisu
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D001769:Blood; D003470:Culture Media; D003786:Dental Pulp Cavity / Q000382:microbiology*; D016521:Electrophoresis, Gel, Pulsed-Field; D013293:Enterococcus faecalis / Q000502:physiology; D016967:Fusobacterium nucleatum / Q000502:physiology; D006171:Gutta-Percha / Q000737:chemistry*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D010485:Periapical Periodontitis / Q000382:microbiology; D016966:Porphyromonas gingivalis / Q000502:physiology; D018713:Prevotella intermedia / Q000502:physiology; D011425:Propionibacterium acnes / Q000502:physiology; D012387:Root Canal Filling Materials / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000502:physiology; D034367:Streptococcus intermedius / Q000502:physiology; D013297:Streptococcus pyogenes / Q000502:physiology; D013298:Streptococcus sanguis / Q000502:physiology; D013499:Surface Properties
chemical_list: D003470:Culture Media; D012387:Root Canal Filling Materials; D006171:Gutta-Percha