Emerging perspectives on the influence of oral biofilm on systemic diseases and clinical implications: beyond oral hygiene

The objective of this review was to evaluate current evidence linking oral biofilm composition and dynamics to the pathogenesis and progression of systemic diseases. We conducted a comprehensive literature search in PubMed, Scopus, Web of Science and the Virtual Health Library, using the terms “oral microbiome,” “biofilm” and “systemic disease” (including diabetes, cardiovascular disease, autoimmune disorders, cancer and neurodegeneration). From 759 retrieved records, 132 high-quality studies were selected for integrative analysis. Our synthesis demonstrates that dysbiotic oral biofilms harboring periodontopathogens such as Porphyromonas gingivalis, Fusobacterium nucleatum and Streptococcus mutans can translocate to distant sites, instigate chronic inflammation, endothelial dysfunction and immune dysregulation. Key mechanisms include lipopolysaccharide-induced cytokine release, quorum-sensing-mediated virulence activation and biofilm-associated evasion of host defenses. Epidemiological and experimental data reveal associations between oral dysbiosis and impaired glycemic control in diabetes, accelerated atherogenesis, exacerbated autoimmune activity, increased risk of head and neck and colorectal cancers, and neuroinflammatory pathways implicated in Alzheimer’s disease. We discuss emerging diagnostic and therapeutic strategies such as metagenomic saliva profiling, targeted antimicrobial peptides, probiotics and host-modulation agents that aim to restore biofilm homeostasis. Integrating oral microbiome assessment into multidisciplinary clinical protocols may enable early identification of at-risk individuals and personalized preventive measures. Further interventional trials are warranted to confirm causality and refine biofilm-focused treatments to enhance both oral and systemic health.