An endodontic conundrum: the association between pulpal infection and periodontal disease.

This paper reviews the classification of periodontal-endodontic lesions and considers the pathways through which inflammatory lesions or bacteria may communicate between the pulp and the periodontium. Such communications have previously underpinned the classification of periodontal-endodontic lesions but a more up-to-date approach is to focus specifically on those lesions that originate concurrently as pulpal infection (and necrosis) and periodontal disease on the affected teeth. In doing so, both conventional periodontal and endodontic treatments are indicated for the affected teeth, although more complex management strategies may occasionally be indicated.