Point-of-Care Biomarker Monitoring of Treatment Efficacy: Changes in Mouthrinse Active Matrix Metalloproteinase-8 (aMMP-8) Concentrations Following Periodontal Anti-Infective Treatment

Introduction The active matrix metalloproteinase-8 (aMMP-8) is a functional biomarker of active periodontal tissue destruction. It bridges the gap between clinical findings and underlying biological processes, providing information on active collagen degradation that conventional clinical examinations do not capture. Methods In a prospective within-subject clinical study, we assessed point-of-care (PoC) mouthrinse aMMP-8 concentrations, periodontal probing depth (PPD), and clinical attachment level (CAL) in 27 adults with stage III/IV (grade C) periodontitis before and 1 month after anti-infective treatment. aMMP-8 PoC results were validated by laboratory western blotting using an independent polyclonal MMP-8 antibody. Results At baseline, 85.2% of samples showed elevated aMMP-8 PoC concentrations, declining to 18.5% post-treatment. Baseline aMMP-8 was significantly associated with disease severity, correlating with both PPD (rs = 0.39, p = 0.045) and CAL (rs = 0.39, p = 0.042). Following treatment, aMMP-8 concentrations decreased significantly (V = 378, p < 0.001), with mean reductions of 78.5 ± 72.6 ng/mL (d = –1.08). Biochemical reductions paralleled clinical improvements, with 100% directional concordance between changes in aMMP-8 and changes in PPD and CAL (95% CI 0.87–1.00). Reductions in aMMP-8 were correlated with improvements in PPD (rs = 0.47, p = 0.014) but not CAL (rs = 0.12, p = 0.544). Linear regression analysis indicated that each 10 ng/mL reduction in aMMP-8 corresponded to an estimated 0.034 mm gain in PPD. Conclusion These findings demonstrate that aMMP-8 PoC monitoring aligns with both baseline disease severity and short-term periodontal healing. aMMP-8 provides an objective biochemical dimension to periodontal assessment, capturing active collagen degradation and serving as a sensitive and clinically meaningful indicator of treatment response.