title: Tenascin-C and matrix metalloproteinase-9 levels in crevicular fluid of teeth and implants.
abstract: BACKGROUND
  The role of and interaction between bacterial infection and biomechanical impact in the development of peri-implant inflammatory processes is not clear.
  
  
  OBJECTIVE
  To determine the amount and concentration of tenascin-C (TNC) in gingival crevicular fluid (GCF) around teeth and in peri-implant sulcus fluid from healthy implants and implants with peri-implantitis, and to correlate it with matrix metalloproteinase-9 (MMP-9) levels.
  
  
  METHODS
  Seven control individuals and 18 patients with 41 implants with/without peri-implantitis were included. GCF was collected with filter strips and volumes were measured with a Periotron device. The amount of serum albumin per sample was quantified by densitometric analysis of Coomassie-stained sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Relative activity of MMP-9 was determined from the densitometry of zymograms. Amounts and concentrations of TNC were evaluated by ELISA.
  
  
  RESULTS
  Relative MMP-9 activity was increased in peri-implantitis. A tendency was observed to measure higher TNC concentrations at teeth than at implants. The amount of TNC in GCF collected from healthy implant sites and the peri-implantitis sites was significantly different. Based on immunoblotting, TNC in GCF seemed degraded. In contrast to TNC, MMP-9 was significantly related to the PD and the volume of GCF.
  
  
  CONCLUSIONS
  TNC is known to be induced in inflammation. The increase found in peri-implantitis was less than expected. In the context of peri-implantitis, TNC might be a marker of bone remodelling rather than inflammation and infection. A possible proteolytic degradation of TNC during peri-implantitis needs to be studied.
authors.affiliation: Department of Prosthodontics, School of Dentistry, University of Bern, Bern, Switzerland.
authors.forename: Ceyda
authors.initials: C
authors.lastname: Özçakır-Tomruk
authors.forename: Matthias
authors.initials: M
authors.lastname: Chiquet
authors.forename: Regina
authors.initials: R
authors.lastname: Mericske-Stern
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015921:Dental Implants / Q000009:adverse effects; D005883:Gingival Crevicular Fluid / Q000737:chemistry* / Q000201:enzymology; D006801:Humans; D020780:Matrix Metalloproteinase 9 / Q000032:analysis / Q000378:metabolism*; D008875:Middle Aged; D057873:Peri-Implantitis / Q000209:etiology / Q000378:metabolism*; D012044:Regression Analysis; D012709:Serum Albumin / Q000378:metabolism; D018709:Statistics, Nonparametric; D019063:Tenascin / Q000032:analysis / Q000378:metabolism*
chemical_list: D015921:Dental Implants; D012709:Serum Albumin; D019063:Tenascin; D020780:Matrix Metalloproteinase 9