Interaction between apical periodontitis and systemic disease (Review).

Apical periodontitis is an oral common inflammatory disease initiated by infection of pulp chamber and is characterized by destruction and resorption of the periapical bone. As a local infection, pathogens and their products in periapical tissues, as well as inflammatory cytokines produced in periapical lesions, enter the blood circulation, triggering systemic immune responses and leading to the pathogenesis of various types of systemic disease. Therefore, apical periodontitis might be associated with systemic disease rather than solely simple local oral disease. In addition, the existence of a hyperinflammatory state in certain patients with chronic inflammation‑related disorder may affect the progression or prognosis of apical periodontitis. However, the association and potential mechanisms between apical periodontitis and systemic diseases remain unclear. An in‑depth understanding of the association between apical periodontitis and systemic disease will be useful for both dentists and physicians to eliminate the possible risk factors and promote the healing of apical periodontitis and systemic disease. Thus, the aim of the present review is to introduce the potential relationship between apical periodontitis and systemic disease.