Inflammation, Hypoxia, and Periodontal Breakdown: The Association Between Obstructive Sleep Apnea and Periodontitis; Results From a Systematic Review With Meta-Analysis

Objective: This systematic review and meta-analysis aimed to evaluate the association between obstructive sleep apnea and periodontitis and to quantify the magnitude of this relationship based on the available evidence. Methods: A systematic literature search was conducted in PubMed, Scopus, and Web of Science up to November 2025, following PRISMA 2020 guidelines. Observational studies investigating the association between OSA and periodontitis in human adults were included. Study quality was assessed using the ROBINS-I tool. A random-effects meta-analysis was performed to pool odds ratios (ORs) with 95% confidence intervals (CIs). Additionally, Spearman correlation coefficients were synthesized when available. Results: Twenty-three studies were included in the qualitative synthesis, and 18 studies were eligible for quantitative analysis. The pooled meta-analysis demonstrated that OSA was significantly associated with an increased risk of periodontitis (OR = 2.22; 95% CI: 1.78–2.77), with moderate heterogeneity (I2 = 57.4%). Furthermore, a random-effects meta-analysis of correlation coefficients revealed a moderate positive association between OSA and periodontal disease severity (r = 0.39; 95% CI: 0.17–0.58). These findings were consistent across different populations and diagnostic approaches, particularly in studies using polysomnography for OSA assessment. Conclusions: The present meta-analysis provides evidence of a significant association between obstructive sleep apnea and periodontitis, with patients affected by OSA showing more than twice the risk of developing periodontal disease. Although causality cannot be established due to the observational nature of the included studies, shared inflammatory and microbiological pathways support a biologically plausible link. An interdisciplinary approach involving dental and sleep medicine professionals may be beneficial for early diagnosis and comprehensive management of both conditions.