title: The effect of photodynamic therapy in root canal disinfection: a systematic review.
abstract: BACKGROUND
  Effective root canal disinfection is a fundamental component of successful root canal treatment. Photodynamic therapy (PDT) has been proposed as a new adjunctive method for additional disinfection of the root canal system with the possibility of improved treatment outcomes. The aim of this systematic review was to investigate the effect of PDT on bacterial load reduction during root canal disinfection.
  
  
  METHODS
  Two reviewers independently conducted a comprehensive literature search using a combination of medical subject heading terms and key words to identify studies relevant to the Population Intervention Control Outcome question. The selection of articles for inclusion was performed in 2 phases based on predetermined eligibility criteria according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Inter-reviewer agreement for each phase was recorded. The effect of PDT on bacterial load reduction during root canal disinfection was evaluated as the primary outcome variable during data extraction.
  
  
  RESULTS
  The literature search provided 57 titles and abstracts. Three articles met the inclusion criteria and were selected for this systematic review. The reasons for study exclusion in each phase were recorded. Because of the heterogeneity in clinical indications and PDT protocols among the included studies, a meta-analysis could not be performed. All included studies showed a positive effect of PDT in the reduction of microbial load in root canal treatment ranging from 91.3%-100%.
  
  
  CONCLUSIONS
  Limited clinical information is currently available on the use of PDT in root canal disinfection. If supported by future clinical research, PDT may have efficacy for additional root canal disinfection, especially in the presence of multi-drug-resistant bacteria.
authors.affiliation: Department of Endodontics, University of Texas Health Science Center at San Antonio, San Antonio, Texas. Electronic address: chrepa@uthscsa.edu.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Chrepa
authors.affiliation: Department of Developmental and Surgical Sciences, University of Minnesota, Minneapolis, Minnesota.
authors.forename: Georgios A
authors.initials: GA
authors.lastname: Kotsakis
authors.affiliation: Division of Endodontics, Harvard School of Dental Medicine, Boston, Massachusetts.
authors.forename: Tom C
authors.initials: TC
authors.lastname: Pagonis
authors.affiliation: Department of Endodontics, University of Texas Health Science Center at San Antonio, San Antonio, Texas.
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Hargreaves
mesh_terms: D058491:Bacterial Load / Q000187:drug effects; D003131:Combined Modality Therapy / Q000379:methods; D003786:Dental Pulp Cavity / Q000187:drug effects / Q000382:microbiology*; D004203:Disinfection / Q000379:methods*; D006801:Humans; D010778:Photochemotherapy / Q000379:methods*; D012388:Root Canal Irrigants / Q000627:therapeutic use*; D018915:Root Canal Preparation / Q000379:methods*
chemical_list: D012388:Root Canal Irrigants
keywords: Antibacterial; bacteria reduction; light-activated disinfection; photodynamic therapy; reactive oxygen species; root canal disinfection