Periodontal Disease in Pets: A Systemic Inflammatory Threat

Periodontal disease is the most prevalent infectious disease in adult dogs and cats, initiated by the accumulation of dental plaque—a biofilm of oral bacteria. If undisturbed, plaque mineralizes into calculus, promoting a shift from aerobic Gram-positive bacteria to pathogenic anaerobic Gram-negative species (e.g., Porphyromonas spp.). The host's immune response to these bacteria, involving neutrophils and macrophages, releases inflammatory mediators and matrix metalloproteinases that destroy the gingiva, periodontal ligament, and alveolar bone. Crucially, periodontal disease is not localized to the oral cavity; the highly vascular periodontium allows bacteria and inflammatory cytokines to enter the systemic circulation (bacteremia). This chronic systemic inflammation has been linked to distant organ pathology, including histological changes in the myocardium, renal interstitium, and hepatic parenchyma.