Oral-Systemic Interactions in Modern Healthcare: A Systematic Review of the Interrelationship Between Dental Pathologies and Systemic Diseases

Periodontitis is a prevalent chronic inflammatory disease characterised by destruction of the supporting structures of the teeth, and increasing evidence indicates that periodontal inflammation and oral microbial dysbiosis contribute to systemic diseases through inflammatory, immune, and vascular mechanisms. This systematic review examined associations between periodontitis and cardiovascular, metabolic, autoimmune, neurological, and inflammatory outcomes in adult populations. Studies published from 2015 onward were identified using a structured literature search, including cohort studies, randomised controlled trials, case-control studies, cross-sectional analyses, Mendelian randomisation studies, and microbiome-based investigations. Due to heterogeneity in study designs and outcomes, qualitative synthesis was performed. Eleven studies met the inclusion criteria, demonstrating consistent associations between periodontitis and increased risk of hypertension, atrial fibrillation, rheumatoid arthritis, dementia, and elevated systemic inflammatory markers. Quantitative findings showed higher blood pressure, increased C-reactive protein levels, greater autoantibody positivity, enhanced inflammasome activity, and reduced oral microbiome diversity in individuals with periodontal disease. Periodontal therapy improved periodontal health and systemic inflammation, although cardiometabolic improvements were modest or inconsistent. The evidence supports periodontitis as a chronic inflammatory condition with significant systemic consequences, mediated by inflammatory, immune, and endothelial pathways, underscoring the importance of integrating periodontal health into disease prevention and management strategies in modern healthcare.