Digital Template-Guided Microapicoectomy In Maxillary First Molar

Microsurgical apicoectomy was performed on the mesiobuccal root of a maxillary left first molar with chronic apical periodontitis and an dislocated separated nickel-titanium (NiTi) instrument, assisted by a 3D-printed digital template. A patient's maxillary first molar experienced fracture of a NiTi instrument during root canal treatment, with the fractured segment extruding beyond the apex of the mesiobuccal (MB) root. Concurrently, the MB2 canal was identified as calcified and non-patent. CBCT imaging revealed: ①The MB root apex near sinus floor; ②Periapical inflammation damaged the sinus floor bone; ③The separated instrument was closely associated with the maxillary sinus. Under microscopic guidance with digital template-assisted navigation: ①The surgical approach avoided perforation of the sinus floor; ②The extruded instrument was successfully retrieved from the periapical region of the MB root; ③Microscopic root-end resection was performed on the MB root. At 1-year follow-up: The tooth remained asymptomatic; CBCT demonstrated thin lamellar bone regeneration at the sinus floor interface. Studies indicate that over 80% of maxillary molars demonstrate close anatomical relationships with the maxillary sinus, with the first and second molars most frequently contacting the sinus. A thorough understanding of this regional anatomy is therefore essential for accurate diagnosis and treatment. For teeth with intact cortical bone adjacent to critical anatomical structures, achieving precise osteotomy and lesion targeting remains a significant clinical challenge. Apical localization guides integrating CBCT and optical scan data provide an effective solution to this dilemma.