Periodontitis and Chronic Liver Disease: Mechanistic Insights Focusing on Porphyromonas gingivalis—A Narrative Review

Porphyromonas gingivalis (P. gingivalis), a keystone pathogen in periodontitis, has been increasingly implicated in compromising hepatic health and exacerbating the pathogenesis of liver diseases, including metabolic dysfunction-associated steatotic liver disease (MASLD), chronic hepatitis, and cirrhosis. Current studies have identified three well-established pathways through which periodontitis contributes to chronic liver disease progression: systemic inflammatory responses, liver cells dysfunction, and gut microbiota dysbiosis. This review systematically elucidates the associations between periodontitis and chronic liver disorders, consolidates evidence on the canonical molecular mechanisms involved, and further proposes potential yet understudied pathways such as ferroptosis, immune evasion, and endothelial–mesenchymal transition (EndMT). By integrating these insights, this work aims to provide novel perspectives for mitigating the systemic adverse effects of periodontitis while offering a theoretical foundation for future research and clinical therapeutic strategies.