[Periodontic-endodontic lesions: diagnostic and therapeutic indications].

The presence of connections between periodontium and endodontium can lead to the diffusion of an infection from one apparatus to another. The involvement of both periodontium and endodontium is defined as Combined Periodontic-Endodontic lesions. This definition is not based on the initial etiology of the lesion and either the endodontic or periodontal lesion may be the cause or the result of the other or both may develop independently. The lesions must be correctly diagnosed for the best therapeutic approach. The diagnosis is based on clinical symptoms and radiographic analysis; clinical signs must show the presence of periodontal probing and pulpal necrosis. Radiographic examination can confirm the involvement of both periodontium and endodontium only if the lesion is present on the mesial and distal part of the diseased tooth; in the case of a palatal/lingual or vestibular lesion such evidence will not be detectable. The therapeutic approach is always based on an initial endodontic treatment followed, if needed, by the proper periodontal treatment.