title: Control of microorganisms in vitro by calcium hydroxide pastes.
abstract: OBJECTIVE
  The aim of this study was to determine the influence of vehicles on the antimicrobial efficiency of calcium hydroxide.
  
  
  METHODS
  A total of 588 size 50 sterile absorbent paper points, were immersed in various microbial suspensions for 3 min. The points were then placed on Petri dishes and covered with intracanal dressings containing calcium hydroxide: Ca(OH)2 + saline; Ca(OH)2 + camphorated paramonochlorophenol; Ca(OH)2 + 1% chlorhexidine solution: Ca(OH)2 + 3% sodium lauryl sulphate; Ca(OH)2 + Otosporin. After 1 min, 48 and 72 h and 7 days, 147 absorbent paper cones were removed from contact with the intracanal dressings and individually transported and immersed in 5 mL of Letheen Broth, followed by incubation at 37 degrees C for 48 h. Microbial growth was evaluated by turbidity of the culture medium. A 0.1-mL inoculum obtained from the Letheen Broth was transferred to 5 mL of BHI, and incubated at 37 degrees C for 48 h. Bacterial growth was again evaluated by turbidity of the culture medium. Positive BHI tubes were selected and inocula were spread on the surface of BHI agar and incubated at 37 degrees C for 48 h. Gram staining of the BHI growth and from colonies growing on BHI agar was carried out.
  
  
  RESULTS
  An antimicrobial effect occurred after 48 h on the cultures of S. mutans, E. faecalis, S. aureus, P aeruginosa, B. subtilis, C. albicans and a mixed culture, irrespective of the intracanal dressing.
  
  
  CONCLUSIONS
  Under the conditions of this study, the various vehicles associated with calcium hydroxide pastes did not influence the time required for microbial inactivation.
authors.affiliation: Department of Endodontics, Federal University of Goiás, Goiânia.
authors.forename: C
authors.initials: C
authors.lastname: Estrela
authors.forename: L L
authors.initials: LL
authors.lastname: Bammann
authors.forename: F C
authors.initials: FC
authors.lastname: Pimenta
authors.forename: J D
authors.initials: JD
authors.lastname: Pécora
mesh_terms: D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects; D002126:Calcium Hydroxide / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects; D013293:Enterococcus faecalis / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D014677:Pharmaceutical Vehicles; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D012388:Root Canal Irrigants / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects; D013295:Streptococcus mutans / Q000187:drug effects
chemical_list: D000891:Anti-Infective Agents, Local; D014677:Pharmaceutical Vehicles; D012388:Root Canal Irrigants; D002126:Calcium Hydroxide