Changes in gingival crevicular fluid matrix metalloproteinase-8 levels during periodontal treatment and maintenance.

OBJECTIVES

The aim of this study was to investigate the effect of scaling and root planing (SRP) and the maintenance phase of treatment on the gingival crevicular fluid (GCF) matrix metalloproteinase-8 (MMP-8) levels.

MATERIALS AND METHODS

Clinical measurements and GCF samples were taken from four sites in 20 adult periodontitis patients before and after SRP and during a 3-month maintenance phase of treatment. MMP-8 levels were measured from GCF samples by time-resolved immunofluorometric assay (IFMA) with monoclonal antibodies.

RESULTS

SRP improved the clinical indices as would be predicted, 6.1 mm (SD = 1.4) at baseline compared with 4.3 mm (SD = 1.6) post-treatment (P < 0.001). Attachment level (AL) reduced but not significantly between these two visits 13.4 mm (SD = 2.4) compared with 12.8 mm (SD = 2.4) (P < 0.08) post therapy. GCF MMP-8 levels reduced after initial treatment from 33.8 micro g/30 s sample to 23.5 micro g/30 s, which just failed to reach statistical significance (P = 0.07). However, when MMP-8 levels were expressed as a concentration, the differences following initial therapy were significant (54.1 ng/ micro L at baseline compared with 34.2 ng/micro L post treatment; P < 0.005). The difference, however, between the baseline MMP-8 levels (33.8 ng/30 s) and the final visit (16 ng/30 s) following maintenance was markedly significant (P < 0.001) for both absolute amounts and on a concentration basis.

CONCLUSION

In conclusion, clinical improvement following SRP was associated with significant reductions in MMP-8 levels. The GCF concentration of MMP-8 decreased after initial therapy but reduced even more dramatically (approximately 50%) following a 3-month period of maintenance (P < 0.001).