title: Clinical significance of dental root canal microflora.
abstract: OBJECTIVE
  Previous work by this group has shown that a significant association exists between pain and the presence of either Prevotella or Peptostreptococcus spp. in dental root canals. The aim of this study was to examine a more extensive series of canals microbiologically, to determine whether any other particular endodontic symptoms or clinical signs showed specific associations with individual bacterial species.
  
  
  METHODS
  Seventy root canals were examined microbiologically and clinical data collected to investigate in detail such associations.
  
  
  RESULTS
  Of the canals studied, 37 were associated with pain, 49 with tenderness to percussion, 23 with swelling, six with purulent exudate and 57 presented with wet root canals. Anaerobes were isolated from 70.3% of painful canals and from 29.7% of pain-free canals. Significant associations were found between (a) pain and either Prevotella spp. or peptostreptococci, both with P < 0.01; (b) tenderness to percussion and Prevotella spp. (P < 0.01) or anaerobes (P < 0.05); (c) swelling and Eubacterium spp. (P < 0.01), or with Prevotella spp. or Pstr. micros, both with P < 0.05; (d) purulent exudate and any one of F. necrophorum (P < 0.01), Prev. loescheii, Streptoccoccus constellatus or Bacteroides spp. (each P < 0.05); (e) wet canal and facultative anaerobes (P < 0.01), and any one of the genera of Eubacterium, Peptostreptococcus, Prevotella or Propionibacterium (each P < 0.05).
  
  
  CONCLUSIONS
  It was concluded that several different endodontic clinical signs and symptoms are significantly associated with specific bacterial species.
authors.affiliation: Restorative Dentistry, University Dental Hospital of Manchester, UK.
authors.forename: B P
authors.initials: BP
authors.lastname: Gomes
authors.forename: J D
authors.initials: JD
authors.lastname: Lilley
authors.forename: D B
authors.initials: DB
authors.lastname: Drucker
mesh_terms: D000328:Adult; D018407:Bacterial Physiological Phenomena; D016866:Bacteroidaceae Infections / Q000175:diagnosis; D001442:Bacteroides Infections / Q000175:diagnosis; D003786:Dental Pulp Cavity / Q000382:microbiology*; D003788:Dental Pulp Diseases / Q000382:microbiology*; D003790:Dental Pulp Necrosis / Q000382:microbiology; D005051:Eubacterium / Q000302:isolation & purification; D005260:Female; D005674:Fusobacterium Infections / Q000175:diagnosis; D005675:Fusobacterium necrophorum / Q000302:isolation & purification; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis; D006801:Humans; D008297:Male; D010462:Peptostreptococcus / Q000302:isolation & purification; D018720:Prevotella / Q000302:isolation & purification; D011424:Propionibacterium / Q000302:isolation & purification; D012390:Root Canal Therapy; D013290:Streptococcal Infections / Q000175:diagnosis; D013492:Suppuration; D014098:Toothache / Q000382:microbiology