title: Cytokine expression in peri-implant crevicular fluid in relation to bacterial presence.
abstract: OBJECTIVE
  The aim was to assess clinical inflammatory parameters, cytokine levels and bacterial counts in samples from implant crevicular fluid in cases with untreated peri-implantitis.
  
  
  METHODS
  Several bacterial species known to up-regulate pro-inflammatory cytokines have been associated with peri-implantitis. The Luminex magnet bead technology was used to study cytokines in crevicular fluid. The checkerboard DNA-DNA hybridization method was used to study bacterial counts in samples from 41 implants (41 individuals).
  
  
  RESULTS
  Profuse bleeding and suppuration was found in 25/41 (61.0%) of the implants. The reliability of duplicate cytokine processing was high. In the presence of profuse bleeding, higher pg/ml levels of IL-1β (p = 0.02), IL-8 (p = 0.04), TNF-α (p = 0.03) and VEGF (p = 0.004) were found. Higher concentrations of IL-1β were found in the presence of suppuration, and if Escherichia coli (p = 0.001) or Staphylococcus epidermidis (p = 0.05) could be detected.
  
  
  CONCLUSIONS
  Profuse bleeding and/or suppuration in untreated peri-implantitis can be associated with higher concentrations of IL-1β, IL-8, TNF-α and VEGF in peri-implant crevicular fluid. A higher concentration of IL-1β in peri-implant crevicular fluid was found in samples that were positive for E. coli or S. epidermidis.
authors.affiliation: Oral Health Sciences, University of Kristianstad, Kristianstad, Sweden.|Blekinge Institute of Technology, Karlskrona, Sweden.|School of Dental Sciences, Trinity College, Dublin, Ireland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Renvert
authors.affiliation: Oral Health Sciences, University of Kristianstad, Kristianstad, Sweden.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Widén
authors.affiliation: Oral Health Sciences, University of Kristianstad, Kristianstad, Sweden.|Department of Periodontics, University of Washington, Seattle, WA, USA.|Department of Oral Medicine, University of Washington, Seattle, WA, USA.
authors.forename: Gösta Rutger
authors.initials: GR
authors.lastname: Persson
mesh_terms: D000328:Adult; D016301:Alveolar Bone Loss / Q000276:immunology / Q000382:microbiology; D001419:Bacteria / Q000276:immunology*; D058491:Bacterial Load; D016207:Cytokines / Q000032:analysis*; D004269:DNA, Bacterial / Q000032:analysis; D015921:Dental Implants / Q000382:microbiology; D004926:Escherichia coli / Q000276:immunology / Q000302:isolation & purification; D005260:Female; D005883:Gingival Crevicular Fluid / Q000276:immunology* / Q000382:microbiology; D005884:Gingival Hemorrhage / Q000276:immunology / Q000382:microbiology; D006801:Humans; D053583:Interleukin-1beta / Q000032:analysis; D016209:Interleukin-8 / Q000032:analysis; D008297:Male; D057873:Peri-Implantitis / Q000276:immunology* / Q000382:microbiology; D010514:Periodontal Pocket / Q000276:immunology / Q000382:microbiology; D013212:Staphylococcus epidermidis / Q000276:immunology / Q000302:isolation & purification; D013492:Suppuration; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis
chemical_list: C508606:CXCL8 protein, human; D016207:Cytokines; D004269:DNA, Bacterial; D015921:Dental Implants; D053583:Interleukin-1beta; D016209:Interleukin-8; D014409:Tumor Necrosis Factor-alpha; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A
keywords: bacteria; cytokines; inflammation; peri-implantitis