The Role of Fusobacterium in Periodontal Disease and Its Implications for Cardiovascular Health

Fusobacterium species, particularly Fusobacterium nucleatum, is known as a key adhesive bridging microorganism in the development of periodontal disease, inducing microbial imbalances and chronic inflammation within the oral cavity. Their role is to provide a bridge between both early colonisers (such as Streptococcus and Actinomyces) and late colonisers (such as Porphyromonas gingivalis and Treponema denticola), which results in multispecies biofilm formation. This triggers an immune reaction which may provide both a protective and destructive effect on the periodontal ligament and alveolar bone. Recent studies have discovered their significance beyond oral pathology. Therefore, Fusobacterium have been implicated in several systemic diseases, including cardiovascular disease (CVD). Virulent mechanisms, such as adhesion, invasion, modulation of host immunity, and pro-inflammatory signalling, contributes to periodontal tissue bone loss and entry into the circulation. Circulating bacteria interact with vascular endothelium and promote atherosclerotic plaque formation. The role of Fusobacterium nucleatum as a microbial link between periodontal disease and cardiovascular disease is highlighted and discussed. Overall, current evidence is mostly observational and preclinical, supporting an associative link between F. nucleatum-mediated periodontal disease and CVD. The literature highlights key mechanistic pathways while underscoring the important need for longitudinal studies to clarify causality and identify target therapeutic interventions.