The Relationship Between Periodontal Diseases and Systemic Health Conditions

Periodontal diseases are chronic inflammatory conditions that affect the gingiva, periodontal ligament, cementum, and alveolar bone and may contribute to the total inflammatory burden of the body. Background: Epidemiological and mechanistic research has linked periodontitis with diabetes, atherosclerotic cardiovascular disease, respiratory disease, adverse pregnancy outcomes, rheumatoid arthritis, chronic kidney disease, and other systemic conditions. Shared risk factors and residual confounding make causal interpretation difficult. Objective: To critically analyse the biological pathways, strength of association, intervention evidence, and practical implications of the relationship between periodontal and systemic diseases. Materials and methods: Narrative synthesis of systematic reviews, consensus reports, cohort studies, randomised trials, and international guidance published from 2012 to 2026. Evidence was classified as association, mechanistic plausibility, or improvement in systemic outcomes after periodontal intervention. Results: The most consistent bidirectional relationship is between periodontitis and diabetes. Non-surgical periodontal therapy may produce a modest short-term improvement in HbA1c, but it does not replace medical treatment. Associations with cardiovascular, respiratory, pregnancy-related, and immune-inflammatory outcomes are clinically relevant but do not prove that periodontal treatment prevents major systemic events. Conclusion: Dental and primary-care professionals should use shared risk assessment, screening, referral, and supportive periodontal care while avoiding exaggerated causal claims.