Retreatment of tooth 2.4 with 3 canals

This patient, ASA 1, was referred for retreatment following reported discomfort on mastication. Clinical examination revealed pain on percussion, with negative response to palpation and normal periodontal probing. CBCT revealed an interradicular radiolucency consistent with periapical inflammatory disease, associated with an untreated canal. The tooth presented a three-canal configuration (two buccal canals and one palatal canal); the second distobuccal canal had not been located during the initial treatment, with only the mesiobuccal and palatal canals having been previously instrumented. Following access cavity preparation, the existing obturation material was removed from the palatal and mesiobuccal canals to allow re-entry into the root canal system. Attention was then directed to locating the missed DB canal, with the help of the pre-op CBCT.…