Local and systemic mechanisms linking periodontal disease and inflammatory comorbidities

Periodontitis has been causally linked to the development of other chronic inflammatory diseases outside the oral mucosa. In this Review, George Hajishengallis and Triantafyllos Chavakis consider the molecular basis of these links. Periodontitis, a major inflammatory disease of the oral mucosa, is epidemiologically associated with other chronic inflammation-driven disorders, including cardio-metabolic, neurodegenerative and autoimmune diseases and cancer. Emerging evidence from interventional studies indicates that local treatment of periodontitis ameliorates surrogate markers of comorbid conditions. The potential causal link between periodontitis and its comorbidities is further strengthened by recent experimental animal studies establishing biologically plausible and clinically consistent mechanisms whereby periodontitis could initiate or aggravate a comorbid condition. This multi-faceted 'mechanistic causality' aspect of the link between periodontitis and comorbidities is the focus of this Review. Understanding how certain extra-oral pathologies are affected by disseminated periodontal pathogens and periodontitis-associated systemic inflammation, including adaptation of bone marrow haematopoietic progenitors, may provide new therapeutic options to reduce the risk of periodontitis-associated comorbidities.

Automated summary

Periodontitis is causally linked to the development of other chronic inflammatory diseases outside the oral mucosa, and intervention studies have shown that local treatment of periodontitis can ameliorate surrogate markers of comorbid conditions. Experimental animal studies have further strengthened the potential causal link by establishing biologically plausible and clinically consistent mechanisms. Understanding the impact of disseminated periodontal pathogens and systemic inflammation associated with periodontitis on extra-oral pathologies may lead to new therapeutic options to reduce the risk of periodontitis-associated comorbidities.