Tenascin-C and Matrix Metalloproteinase-9 Levels in Crevicular Fluid of Teeth and Implants

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. Materials and 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 sulfatepolyacrylamide 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. Conclusion: 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.