Partial Necrosis Consequence of the Infection Spreading from an Adjacent Apical Periodontitis: A Case Report.

As the dental pulp could not be directly inspected before endodontic treatment, indirect evaluation of the pulp status via (para)/clinical tests should be performed which need careful inspection. This report presents a root-treated right maxillary first molar with recurrent abscess formation and a radiolucent periradicular lesion surrounding the distobuccal root of the right maxillary second molar. The patient underwent surgical retreatment, employing CEM root-end filling, which resulted in no relief from sign/symptoms. In the cone-beam computed tomography (CBCT), the relationship of the lesion with the mesio-buccal root of the second maxillary molar was detected. Despite the latest tooth showed positive responses to pulp sensibility tests, endodontic therapy was planned for it. During treatment, it became clear that the mesiobuccal canal pulp was necrotic, although vital pulp tissues were present in two other root canals. Following treatment, full recovery from all discomforts was obtained and the lesion healed after 18 months. This case showed that a more complicated evaluation such as CBCT should be used for diagnosis of perpetuated lesions. Furthermore, it might be probable that root canals of vital teeth become necrotic due to involvement in the adjacent apical lesion, a phenomenon known as anachoresis.