Effect of Initial Periodontal Therapy on MMPs in Aggressive Periodontitis

Objective: The aim of this study was to evaluate the effects of phase I periodontal treatment on gingival crevicular fluid (GCF) levels of matrix metalloproteinases (MMP-1, 2, 3, 8, 9, 12, 13) from an aggressive periodontitis (AgP) cohort ranging in age from 13-19 yrs.

Methods: Ten AgP patients and 12 healthy, age-matched controls were included in this study. GCF samples were collected from two ‘deep' sites (PD 5-8 mm with bleeding on probing) in each AgP subject at baseline; these same sites were re-sampled at 6 weeks following phase I periodontal treatment. Two ‘shallow' sites (PD=2mm) in each healthy subject were sampled at baseline as controls. GCF volume was determined with a calibrated gingival fluid meter, and MMPs were detected and quantified fluorimetrically. MMP values for each site were converted to concentration (ng/uL) before non-parametric statistical analysis was employed.

Results: Nonsurgical periodontal therapy led to a significant reduction (p<0.01) of MMP concentrations at 6 weeks post-therapy relative to baseline, with the exception of MMP-12. The collagenases, MMP-1, 8, and 13, were reduced by factors of 5.0, 4.0, and 5.5, respectively, and demonstrated strong correlation ratios with each together (r>0.9). The gelatinases, MMP-2 and 9, demonstrated a strong correlation ratio (r=0.87) with each other and a 2-fold reduction in MMP levels. None of the MMPs measured demonstrated a strong correlation with PD at baseline, yet all demonstrated much stronger correlation after treatment (r>0.70). Interestingly, although MMP-12 levels did not differ significantly from baseline, it showed the lowest correlation with PD at baseline (r=0.1) and the highest correlation after treatment (r=0.8).

Conclusions: These findings suggest that phase I periodontal therapy provides a reduction in MMP levels in GCF of AgP subjects. These levels, with the exception of MMP-13, were still significantly elevated relative to healthy controls.