Nonsurgical approach of multiple complications in a retreatment of an upper right first molar

Pre-operative periapical x-ray Diagnosis (AAE&ESE) Pupal: previously obturated root canal Periapical: localized symptomatic apical periodontitis Initial PA x-ray, before referral intervened Pre-operative small FOV CBCT to assess complications and establish retreatment plan (as per AAE and AAOMR Joint Position Statement of Use of Cone Beam Computed Tomography in Endodontics) Pre-operative clinical aspect (initial isolation with split dam technique) Removal of temporary restoration materials and remaining caries followed by refining the pulp chamber space and sound dental tissues Pre-endodontic build-up Change of isolation by single tooth (liquid dam to reinforce gingival margin seal) Removal of separated instrument from the MB system (US and U-files) Intra-operative PA x-ray to verify complete removal of previously separated instrument and all root canal filling materials…