title: Microbiota of deciduous endodontic infections analysed by MDA and Checkerboard DNA-DNA hybridization.
abstract: OBJECTIVE
  To evaluate the microbiota of endodontic infections in deciduous teeth by Checkerboard DNA-DNA hybridization after uniform amplification of DNA in samples by multiple displacement amplification (MDA).
  
  
  METHODS
  Forty samples from the root canal system of deciduous teeth exhibiting pulp necrosis with or without radiographically detectable periradicular/interradicular bone resorption were collected and 32 were analysed, with three individuals contributing two samples; these were MDA-amplified and analysed by Checkerboard DNA-DNA hybridization for levels of 83 bacterial taxa. Two outcome measures were used: the percentage of teeth colonized by each species and the mean proportion of each bacterial taxon present across all samples.
  
  
  RESULTS
  The mean amount of DNA in the samples prior to amplification was 5.2 (±4.7) ng and 6.1 (±2.3) μg after MDA. The mean number of species detected per sample was 19 (±4) (range: 3-66) to the nearest whole number. The most prevalent taxa were Prevotella intermedia (96.9%), Neisseria mucosa (65.6%), Prevotella nigrescens (56.2%) and Tannerella forsythia (56.2%). Aggregatibacter (Haemophilus) aphrophilus and Helicobacter pylori were not detected. P. intermedia (10%), Prevotella tannerae (7%) and Prevotella nigrescens (4.3%) presented the highest mean proportions of the target species averaged across the positive samples.
  
  
  CONCLUSIONS
  Root canals of infected deciduous teeth had a diverse bacterial population. Prevotella sp. were commonly found with P. intermedia, Prevotella tannerae and Prevotella nigrescens amongst the most prominent species detected.
authors.affiliation: Federal University of Minas Gerais School of Dentistry, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: W L F
authors.initials: WL
authors.lastname: Tavares
authors.forename: L C
authors.initials: LC
authors.lastname: Neves de Brito
authors.forename: R P
authors.initials: RP
authors.lastname: Teles
authors.forename: M L A
authors.initials: ML
authors.lastname: Massara
authors.forename: A P
authors.initials: AP
authors.lastname: Ribeiro Sobrinho
authors.forename: A D
authors.initials: AD
authors.lastname: Haffajee
authors.forename: S S
authors.initials: SS
authors.lastname: Socransky
authors.forename: F R
authors.initials: FR
authors.lastname: Teles
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D001431:Bacteriological Techniques / Q000379:methods; D002648:Child; D002675:Child, Preschool; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000032:analysis*; D003786:Dental Pulp Cavity / Q000382:microbiology*; D003790:Dental Pulp Necrosis / Q000382:microbiology*; D006801:Humans; D021141:Nucleic Acid Amplification Techniques / Q000379:methods; D009693:Nucleic Acid Hybridization / Q000379:methods; D014094:Tooth, Deciduous / Q000382:microbiology*
chemical_list: D004269:DNA, Bacterial