title: Effectiveness of repeated photodynamic therapy in the elimination of intracanal Enterococcus faecalis biofilm: an in vitro study.
abstract: The study aimed to investigate the effectiveness of photodynamic therapy in the elimination of intracanal Enterococcus faecalis biofilm and to analyse how a repeated light irradiation, replenishment of oxygen and photosensitiser affect the results of the photodynamic disinfecting protocol. After chemomechanical preparation, 46 single-rooted human teeth were infected with a clinical strain of E. faecalis and incubated for a week in microaerobic conditions. The experimental procedures included groups of single application of photodynamic therapy, two cycles of PDT, irrigation with 5.25% NaOCl solution and negative and positive control. The number of residing bacterial colonies in the root canals was determined based on the CFU/ml method. In the group of preparations irrigated with NaOCl, bacterial colonies were not observed. A single PDT eliminated 45% of the initial CFU/ml. Repeated PDT eradicated 95% of the intracanal bacterial biofilm. Photodynamic therapy has a high potential for the elimination of E. faecalis biofilm. There is a safe therapeutic window where photoinduced disinfection can be used as an adjuvant to conventional endodontic treatment, which remains the most effective.
authors.affiliation: Department of Conservative Dentistry, Medical University of Warsaw, Miodowa Street 18, 02-797, Warsaw, Poland. ewagg@interia.eu.
authors.forename: Ewa Joanna
authors.initials: EJ
authors.lastname: Prażmo
authors.affiliation: Department of Bacterial Genetics, Faculty of Biology, University of Warsaw, Miecznikowa Street 1, 02-096, Warsaw, Poland.
authors.forename: Renata Alicja
authors.initials: RA
authors.lastname: Godlewska
authors.affiliation: Department of Conservative Dentistry, Medical University of Warsaw, Miodowa Street 18, 02-797, Warsaw, Poland.
authors.forename: Agnieszka Beata
authors.initials: AB
authors.lastname: Mielczarek
mesh_terms: D000328:Adult; D018441:Biofilms / Q000187:drug effects / Q000528:radiation effects*; D015169:Colony Count, Microbial; D003786:Dental Pulp Cavity / Q000187:drug effects / Q000382:microbiology* / Q000528:radiation effects; D004203:Disinfection; D013293:Enterococcus faecalis / Q000254:growth & development / Q000302:isolation & purification / Q000528:radiation effects*; D006801:Humans; D008297:Male; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000494:pharmacology; D018915:Root Canal Preparation / Q000379:methods; D016896:Treatment Outcome
chemical_list: D017319:Photosensitizing Agents
keywords: Endodontic disinfection; Enterococcus faecalis; PDT; Photodynamic