title: Effectiveness of photodynamic therapy against Enterococcus faecalis, with and without the use of an intracanal optical fiber: an in vitro study.
abstract: OBJECTIVE
  Photodynamic therapy (PDT) is a new technique introduced in endodontics that combines the action of a photosensitizer (dye) and a low intensity light source. Currently, there are no PDT studies evaluating the microbial disinfection of root canals in order to compare the effects of light delivery systems in the photosensitizer activation. The aim of this study was to evaluate the PDT effectiveness in reducing Enterococcus faecalis, with and without the aid of an intracanal optical fiber.
  
  
  METHODS
  Extracted single-rooted teeth were selected, instrumented, inoculated with E. faecalis and divided into six groups: one control group (untreated), one conventionally-treated group (1% NaOCl irrigation) and four PDT-treated groups. Irradiation (diode laser) was performed with (OF) or without an intracanal optical fiber (NOF) using two different irradiation times: 1 min and 30 sec (IT(90)) or 3 min (IT(180)). Samples were collected before and after testing procedures and CFU/mL was determined.
  
  
  RESULTS
  The greatest reduction of E. faecalis (99.99%) was achieved with irrigation with 1% NaOCl. PDT also significantly reduced E. faecalis in the following decreasing order: OF/IT(180), NOF/IT(180), OF/IT(90) and NOF/IT(90), with no significant statistical difference among the groups.
  
  
  CONCLUSIONS
  These results suggest that PDT was effective against E. faecalis, regardless of the use of an intracanal optical fiber.
authors.affiliation: Department of Endodontics, University of Taubaté, São Paulo, Brazil.
authors.forename: Maralize Ribeiro
authors.initials: MR
authors.lastname: Nunes
authors.forename: Isabel
authors.initials: I
authors.lastname: Mello
authors.forename: Gilson Cesar Nobre
authors.initials: GC
authors.lastname: Franco
authors.forename: João Marcelo Ferreira
authors.initials: JM
authors.lastname: de Medeiros
authors.forename: Silvana Soléo Ferreira
authors.initials: SS
authors.lastname: Dos Santos
authors.forename: Sandra Márcia
authors.initials: SM
authors.lastname: Habitante
authors.forename: José Luiz
authors.initials: JL
authors.lastname: Lage-Marques
authors.forename: Denise Pontes
authors.initials: DP
authors.lastname: Raldi
mesh_terms: D003786:Dental Pulp Cavity / Q000382:microbiology*; D004202:Disinfectants / Q000494:pharmacology; D004203:Disinfection / Q000379:methods; D013293:Enterococcus faecalis / Q000187:drug effects*; D006801:Humans; D066298:In Vitro Techniques; D055100:Optical Fibers; D010778:Photochemotherapy / Q000379:methods*; D018915:Root Canal Preparation / Q000379:methods; D012973:Sodium Hypochlorite / Q000494:pharmacology; D018709:Statistics, Nonparametric; D007507:Therapeutic Irrigation / Q000379:methods
chemical_list: D004202:Disinfectants; D012973:Sodium Hypochlorite