title: Protein biomarkers and microbial profiles in peri-implantitis.
abstract: OBJECTIVE
  The aim of the present investigation was to determine the profile of peri-implant crevicular fluid (PICF) biomarkers combined with microbial profiles from implants with healthy peri-implant tissues and peri-implantitis to assess real-time disease activity.
  
  
  METHODS
  Sixty-eight patients were included in this cross-sectional study. They were divided into two groups: 34 patients with at least one healthy implant (control) and 34 with at least one peri-implantitis affected implant (test). Total DNA content and qPCR analysis for periodontal bacteria obtained from subgingival plaque samples (Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola) and a PICF analysis for IL-1β, VEGF, MMP-8, TIMP-2, and OPG were performed. The individual and combined diagnostic ability of each biomarker for peri-implantitis and target bacterial species were analyzed.
  
  
  RESULTS
  The mean concentration of IL-1β (44.6 vs. 135.8 pg/ml; P < 0.001), TIMP-2 (5488.3 vs. 9771.8 pg/ml; P = 0.001), VEGF (59.1 vs. 129.0 pg/ml; P = 0.012), and OPG (66.5 vs. 111.7 pg/ml; P = 0.050) was increased in the peri-implantitis patients. The mean expression of MMP-8 (6029.2 vs. 5943.1 pg/ml; P = 0.454) and did not reveal a meaningful difference among groups. Total bacterial DNA of selected microorganisms was associated with a threefold or greater increase in peri-implantitis although no statistical significant difference. The ability to diagnose diseased sites was enhanced by T. denticola combined with IL-1β, VEGF, and TIMP-2 PICF levels.
  
  
  CONCLUSIONS
  The present data suggest that the increased levels of the selected PICF-derived biomarkers of periodontal tissue inflammation, matrix degradation/regulation, and alveolar bone turnover/resorption combined with site-specific microbial profiles may be associated with peri-implantitis and could have potential as predictors of peri-implant diseases.
authors.affiliation: Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.
authors.forename: Hom-Lay
authors.initials: HL
authors.lastname: Wang
authors.affiliation: Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.
authors.forename: Carlos
authors.initials: C
authors.lastname: Garaicoa-Pazmino
authors.affiliation: Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.
authors.forename: Amy
authors.initials: A
authors.lastname: Collins
authors.affiliation: Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.
authors.forename: Hwen-Sei
authors.initials: HS
authors.lastname: Ong
authors.affiliation: Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.
authors.forename: Rini
authors.initials: R
authors.lastname: Chudri
authors.affiliation: Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.
authors.forename: William V
authors.initials: WV
authors.lastname: Giannobile
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D003430:Cross-Sectional Studies; D005260:Female; D005883:Gingival Crevicular Fluid / Q000737:chemistry; D005889:Gingival Recession / Q000382:microbiology; D006801:Humans; D053583:Interleukin-1beta / Q000032:analysis; D008297:Male; D020784:Matrix Metalloproteinase 8 / Q000032:analysis; D008875:Middle Aged; D053244:Osteoprotegerin / Q000032:analysis; D057873:Peri-Implantitis / Q000378:metabolism / Q000382:microbiology*; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000032:analysis; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis
chemical_list: D015415:Biomarkers; D053583:Interleukin-1beta; D053244:Osteoprotegerin; D042461:Vascular Endothelial Growth Factor A; D019716:Tissue Inhibitor of Metalloproteinase-2; D020784:Matrix Metalloproteinase 8
keywords: dental implant microbiology; peri-implant crevicular fluid; peri-implant disease; salivary diagnostics