Impact of a Dietary Supplementation with French Maritime Pine Bark Extract Pycnogenol® on Salivary and Serum Inflammatory Biomarkers During Non-Surgical Periodontal Therapy—A Randomized Placebo-Controlled Double-Blind Trial

Background: Periodontal disease and gingival inflammation are globally highly prevalent and may entail distal consequences on systemic health. While professional mechanical plaque removal (PMPR) is the standard treatment, dietary interventions may provide additional benefits. The French maritime pine bark extract Pycnogenol® has anti-inflammatory and antioxidant properties, but its impact on inflammatory biomarkers in saliva and serum has not been studied in a controlled clinical trial. Methods: In this randomized, double-blind, placebo-controlled clinical trial, a total of 91 participants received Pycnogenol® (100 mg twice daily; n = 46) or a placebo (n = 45) following PMPR. Saliva and serum samples were collected at baseline, and after two and three months. Biomarkers associated with inflammation (IL-1β, IL-6, MMP-8, MMP-9) and polyphenol concentrations were analyzed using enzyme-linked immunosorbent assays (ELISA) and liquid chromatography-tandem mass spectrometry (LCMS/MS). Results: Pycnogenol® supplementation resulted in a significant reduction in salivary MMP8 levels (p = 0.0261), and lower serum IL-6 levels compared to placebo after three months (p = 0.0409). Additionally, ferulic acid, caffeic acid, and the gut microbial metabolite 5-(3,4-dihydroxyphenyl)-γ-valerolactone (M1) significantly increased in saliva following Pycnogenol® intake. Correlation analysis revealed a significant inverse association between the percentage of bleeding on probing and M1 concentration in saliva (r = -0.3476, p = 0.0167). Conclusion: Dietary supplementation with Pycnogenol® significantly reduced key inflammatory biomarkers and increased polyphenol concentrations in saliva. These findings suggest a potential anti-inflammatory effect of Pycnogenol® on gingival inflammation.