title: Diversity of Enterococcus faecalis Genotypes from Multiple Oral Sites Associated with Endodontic Failure Using Repetitive Sequence-based Polymerase Chain Reaction and Arbitrarily Primed Polymerase Chain Reaction.
abstract: BACKGROUND
  The aim of this study was to evaluate the diversity and similarity of Enterococcus faecalis genotype isolates from multiple oral sites using repetitive sequence-based polymerase chain reaction and arbitrarily primed polymerase chain reaction (AP-PCR).
  
  
  METHODS
  Forty-two endodontically treated teeth with apical periodontitis were selected. A total of 126 microbial samples were collected from 3 different sites (saliva, pulp chamber, and root canals, all n = 42) during the nonsurgical retreatment procedures. After growth on m-Enterococcus agar, the colonies were isolated, characterized as gram-positive catalase negative cocci, and identified using an API 20 Strep kit (bioMérieux, Marcy-l'Etoile, France). Seventy-four colonies from 10 patients were confirmed as E. faecalis by polymerase chain reaction (16S ribosomal RNA). Repetitive sequence-based polymerase chain reactions using ERIC and AP-PCR using RW3A primers were performed in all 74 colonies. Fingerprints were analyzed and separated into genotypic groups based on the Dice coefficient percentage of similarity (82% or greater) as determined by ERIC reproducibility assays involving E. faecalis controls.
  
  
  RESULTS
  Seven different E. faecalis genotypes (GTs) (GT1 = 27%, GT2 = 17.6%, GT3 = 1.3%, GT4 = 18.9%, GT5 = 9.5%, GT6 = 14.9%, and GT7 = 10.8%) were observed in different subjects and oral sites associated with endodontic failure. Remarkably, in 4 of 5 patients, the same GTs present in the infected root canals were also isolated from either the pulp chamber or the saliva samples. In particular, GT6 was detected in all 3 oral sites of patient 37.
  
  
  CONCLUSIONS
  E. faecalis GTs isolated from saliva, the pulp chamber, and the root canal were similar using the Rep-PCR and AP-PCR methods. These findings suggest that coronal microleakage is a conceivable cause of endodontic failure.
authors.affiliation: College of Dentistry, Facid DeVry University, Teresina, Piauí, Brazil; Department of Restorative Dentistry, Endodontic Division, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Maraísa G
authors.initials: MG
authors.lastname: Delboni
authors.affiliation: Department of Restorative Dentistry, Endodontic Division, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil. Electronic address: bpgomes@unicamp.br.
authors.forename: Brenda P F A
authors.initials: BP
authors.lastname: Gomes
authors.affiliation: Department of Restorative Dentistry, Endodontic Division, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Priscila A
authors.initials: PA
authors.lastname: Francisco
authors.affiliation: Department of Endodontics, Dows Institute for Dental Research, College of Dentistry, University of Iowa, Iowa City, Iowa.
authors.forename: Fabrício B
authors.initials: FB
authors.lastname: Teixeira
authors.affiliation: Department of Endodontics, Dows Institute for Dental Research, College of Dentistry, University of Iowa, Iowa City, Iowa.
authors.forename: David
authors.initials: D
authors.lastname: Drake
mesh_terms: D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000032:analysis; D003786:Dental Pulp Cavity / Q000382:microbiology*; D013293:Enterococcus faecalis / Q000235:genetics* / Q000302:isolation & purification; D005838:Genotype; D006801:Humans; D010485:Periapical Periodontitis / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D012091:Repetitive Sequences, Nucleic Acid; D012463:Saliva / Q000382:microbiology*; D019553:Tooth, Nonvital / Q000382:microbiology*; D017211:Treatment Failure
chemical_list: D004269:DNA, Bacterial
keywords: Arbitrarily primed polymerase chain reaction; Enterococcus faecalis; endodontics; microleakage; microorganisms; repetitive sequence-based polymerase chain reaction; saliva