title: Differences in prevalence of selected bacterial species in primary endodontic infections from two distinct geographic locations.
abstract: OBJECTIVE
  This study intended to compare the prevalence of 7 putative endodontic pathogens in samples of primary endodontic infections taken from patients of 2 distant geographic locations.
  
  
  METHODS
  Samples from infected root canals associated with asymptomatic periradicular lesions or from pus aspirated from acute periradicular abscesses were collected from patients in Rio de Janeiro, Brazil, and Seoul, South Korea. South Korean samples were frozen and delivered to Brazil, where all steps in the molecular analysis were performed. DNA was extracted and a species-specific nested polymerase chain reaction assay was used to detect 7 target bacterial species.
  
  
  RESULTS
  The most prevalent species detected in Brazilian samples were Porphyromonas endodontalis (79% of the cases) , Treponema denticola (79%), and Dialister pneumosintes (76%). The most prevalent species found in South Korean samples were Fusobacterium nucleatum (38% of the cases) , Tannerella forsythia (26%), and Treponema maltophilum (24%). Overall, P endodontalis, D pneumosintes, Filifactor alocis, T denticola, and T forsythia were significantly more detected in Brazilian samples than in South Korean samples ( P < .05).
  
  
  CONCLUSIONS
  Findings indicated that the prevalence of some species in infections of endodontic origin may significantly differ from one geographic location to another.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Estácio de Sá University, Federal University of Rio de Janeiro, Brazil. siqueira@estacio.br
authors.forename: José F
authors.initials: JF
authors.lastname: Siqueira
authors.forename: Il-Young
authors.initials: IY
authors.lastname: Jung
authors.forename: Isabela N
authors.initials: IN
authors.lastname: Rôças
authors.forename: Chan-Young
authors.initials: CY
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015373:Bacterial Typing Techniques; D001439:Bacteroides / Q000302:isolation & purification; D001938:Brazil; D016009:Chi-Square Distribution; D004269:DNA, Bacterial / Q000032:analysis; D005673:Fusobacterium / Q000302:isolation & purification; D016965:Gram-Negative Anaerobic Straight, Curved, and Helical Rods / Q000302:isolation & purification; D006801:Humans; D007723:Korea; D008875:Middle Aged; D017720:Molecular Epidemiology; D010485:Periapical Periodontitis / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods; D045202:Porphyromonas endodontalis / Q000302:isolation & purification; D014208:Treponema / Q000302:isolation & purification
chemical_list: D004269:DNA, Bacterial