title: Oral microbiota species in acute apical endodontic abscesses.
abstract: OBJECTIVE
  Acute apical abscesses are serious endodontic diseases resulting from pulpal infection with opportunistic oral microorganisms. The objective of this study was to identify and compare the oral microbiota in patients (N=18) exhibiting acute apical abscesses, originating from the demographic region in Portland, Oregon. The study hypothesis is that abscesses obtained from this demographic region may contain unique microorganisms not identified in specimens from other regions.
  
  
  METHODS
  Endodontic abscesses were sampled from patients at the Oregon Health & Science University (OHSU) School of Dentistry. DNA from abscess specimens was subjected to polymerase chain reaction amplification using 16S rRNA gene-specific primers and Cy3-dCTP labeling. Labeled DNA was then applied to microbial microarrays (280 species) generated by the Human Oral Microbial Identification Microarray Laboratory (Forsyth Institute, Cambridge, MA).
  
  
  RESULTS
  The most prevalent microorganisms, found across multiple abscess specimens, include Fusobacterium nucleatum, Parvimonas micra, Megasphaera species clone CS025, Prevotella multisaccharivorax, Atopobium rimae, and Porphyromonas endodontalis. The most abundant microorganisms, found in highest numbers within individual abscesses, include F. nucleatum, P. micra, Streptococcus Cluster III, Solobacterium moorei, Streptococcus constellatus, and Porphyromonas endodontalis. Strong bacterial associations were identified between Prevotella multisaccharivorax, Acidaminococcaceae species clone DM071, Megasphaera species clone CS025, Actinomyces species clone EP053, and Streptococcus cristatus (all with Spearman coefficients >0.9).
  
  
  CONCLUSIONS
  Cultivable and uncultivable bacterial species have been identified in endodontic abscesses obtained from the Portland, Oregon demographic region, and taxa identifications correlated well with other published studies, with the exception of Treponema and Streptococcus cristae, which were not commonly identified in endodontic abscesses between the demographic region in Portland, Oregon and other regions.
authors.affiliation: Academic DMD Program, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Noelle
authors.initials: N
authors.lastname: George
authors.affiliation: Academic DMD Program, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Erin
authors.initials: E
authors.lastname: Flamiatos
authors.affiliation: Academic DMD Program, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Kellie
authors.initials: K
authors.lastname: Kawasaki
authors.affiliation: Academic DMD Program, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Namgu
authors.initials: N
authors.lastname: Kim
authors.affiliation: Academic DMD Program, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Charles
authors.initials: C
authors.lastname: Carriere
authors.affiliation: Academic DMD Program, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Phan
authors.affiliation: Academic DMD Program, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Raphael
authors.initials: R
authors.lastname: Joseph
authors.affiliation: Department of Integrative Biosciences, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Shay
authors.initials: S
authors.lastname: Strauss
authors.affiliation: Department of Community Dentistry, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Richie
authors.initials: R
authors.lastname: Kohli
authors.affiliation: Department of Community Dentistry, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.|School of Public Health, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Dongseok
authors.initials: D
authors.lastname: Choi
authors.affiliation: Department of Endodontology, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: J Craig
authors.initials: JC
authors.lastname: Baumgartner
authors.affiliation: Department of Endodontology, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Sedgley
authors.affiliation: Department of Integrative Biosciences, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.|Department of Pathology and Radiology, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.
authors.forename: Tom
authors.initials: T
authors.lastname: Maier
authors.affiliation: Department of Integrative Biosciences, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA.|Department of Pediatric Dentistry, School of Dentistry, Oregon Health & Science University (OHSU), Portland, OR, USA; machidac@ohsu.edu.
authors.forename: Curtis A
authors.initials: CA
authors.lastname: Machida
keywords: Fusobacterium nucleatum; Streptococcus cristatus; anaerobic oral microorganisms; endodontic abscesses; human oral microbial identification microarrays; oral microbiota