Objective: To compare collagenase activity and collagenolytic matrix metalloproteinase (MMP) levels in gingival crevicular fluid (GCF) and in peri-implant sulcular fluid (PISF) in gingivitis (G), chronic periodontitis (CP), and peri-implantitis (PI) human subjects.
Material and methods: GCF and PISF were collected on filter paper strips, volume was determined, and samples were extracted in buffer containing general proteinase but not MMP inhibitors. Collagenase activity was measured using a DNP-synthetic octapeptide, and molecular and activation forms of collagenase-2 by Western immunoblotting.
Results: GCF from CP and G sites exhibited elevated collagenase activity and flow, but collagenase concentrations expressed per microl were not significantly different between the healthy and G sites. Minimal fluid was obtained from healthy PISF, and collagenase concentration was the same or lower than in healthy GCF. Although PISF flow was 34% lower than GCF flow in CP subjects, collagenase concentration in CP and in PI sites was 78% and 971% greater, respectively, than in the appropriate healthy sites. Western immunoblot revealed MMP-8 in both PISF and GCF; fibroblast-type MMP-8 was not detected in healthy GCF and PISF. Immunoreactivity level and inactive and activated forms of PMN-type MMP-8 in GCF and PISF increased with the severity of periodontitis and peri-implantitis. Enhanced levels of fibroblast-type MMP-8 in active form were detected only in severe CP GCF and PI PISF.
Conclusions: Peri-implantitis PISF contained higher collagenase-2 levels and activity than GCF from similar deep CP sites. GCF and PISF from severe CP and PI exhibited the highest activation of MMP-8 isoenzymes species (PMN and fibroblast-type).