title: Dialister pneumosintes can be a suspected endodontic pathogen.
abstract: OBJECTIVE
  Dialister pneumosintes is a nonmotile, nonfermentative, non-spore-forming, obligately anaerobic, gram-negative bacillus that has been associated with some infections in the human body. A species-specific nested polymerase chain reaction assay was used to investigate the occurrence of D pneumosintes in primary root canal infections.
  
  
  METHODS
  Samples were collected from 32 teeth with carious lesions, necrotic pulps, and radiographic evidence of periradicular bone destruction. Twenty-two teeth were asymptomatic, and 10 cases were diagnosed as acute apical periodontitis. DNA extracted from the samples was initially amplified with universal 16S ribosomal DNA primers. A second round of amplification used the first polymerase chain reaction products to specifically detect D pneumosintes.
  
  
  RESULTS
  This bacterial species was detected in 17 of 22 asymptomatic cases (77.3%) and in 4 of 10 root canals associated with acute apical periodontitis (40%). No relationship was found between the presence of this bacterial species and the occurrence of symptoms. In general, D pneumosintes was detected in 21 of 32 root canal samples (65.6%).
  
  
  CONCLUSIONS
  This study is the first to report a high prevalence of D pneumosintes in root canal infections of humans. Because of this high prevalence and the apparent pathogenicity of the microorganism, we suggest the inclusion of D pneumosintes in the selected group of putative endodontic pathogens.
authors.affiliation: Department of Endodontics, Estácio de Sá University, Rio de Janeiro, Brazil. siqueira@estacio.br
authors.forename: José F
authors.initials: JF
authors.lastname: Siqueira
authors.forename: Isabela N
authors.initials: IN
authors.lastname: Rôças
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D016009:Chi-Square Distribution; D004269:DNA, Bacterial / Q000235:genetics; D003731:Dental Caries / Q000382:microbiology; D003786:Dental Pulp Cavity / Q000382:microbiology*; D003788:Dental Pulp Diseases / Q000382:microbiology*; D003790:Dental Pulp Necrosis / Q000382:microbiology; D016965:Gram-Negative Anaerobic Straight, Curved, and Helical Rods / Q000145:classification* / Q000235:genetics / Q000472:pathogenicity; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis*; D006801:Humans; D008875:Middle Aged; D010485:Periapical Periodontitis / Q000382:microbiology; D016133:Polymerase Chain Reaction; D014774:Virulence
chemical_list: D004269:DNA, Bacterial