Aim: To make an initial assessment of the periodontal diagnostic potential of immunoreactive matrix metalloproteinase-8 (MMP-8) in gingival crevicular fluid (GCF) by comparison with elastase activity which has previously been associated with disease severity and progression.
Methods: GCF was collected from molar and premolar sites of 16 chronic adult periodontitis patients before treatment and 13 of this group 2 weeks after scaling and root planing. Samples were analysed for MMP-8 by immunofluorometric assay and for elastase activity with a fluorogenic substrate.
Results: Mean patient clinical parameters and GCF enzyme totals both decreased significantly after treatment. Total MMP-8 levels and elastase activities generally correlated significantly with gingival and bleeding indices. For GCF concentrations, only MMP-8 showed a significant fall after treatment, and some significant correlations with clinical parameters. Amounts of the 2 enzymes correlated significantly with each other.
Conclusions: Similarities between MMP-8 and elastase probably reflect the fact that both enzymes are associated mainly with neutrophils: MMP-8 levels may have fallen more after treatment because the assay, unlike that for elastase, would most likely not have detected much enzyme bound to alpha-macroglobulin. The immunoassay for MMP-8 is more specific and convenient than functional collagenase assays, and might be suitable for monitoring the periodontal condition.