Rapid Alteration of Buccal Cortical Bone following Acute Apical Abscess: Implications for Endodontic Microsurgery: A Case Report

Introduction: In endodontic microsurgery, cone-beam computed tomography (CBCT) imaging serves as a roadmap for assessing buccal cortical bone thickness and planning the osteotomy. However, periapical lesions are dynamic in nature. This case report describes a discrepancy between preoperative CBCT findings, and the surgical anatomy observed after an acute apical abscess. Case Report: A 25-year-old female presented with persistent pain and swelling in the area of tooth #19 (mandibular first molar). Initial CBCT (T₀) showed a relatively thick buccal cortical plate overlying the periapical lesion, with no apparent cortical perforation in the available images. After an acute flare-up with severe swelling just before the scheduled surgery, intraoperative observation revealed extensive buccal cortical fenestration. The surgery was completed under microscopy, including retrieval of a separated file, isthmus preparation, and retrograde root-end filling with a bioceramic material (NeoPutty, Avalon Biomed, Houston, TX, USA). At the one-year follow-up, the periapical radiograph demonstrated substantial radiographic healing. Conclusion: This case highlights a discrepancy between preoperative CBCT findings, and the cortical anatomy encountered during surgery following an acute inflammatory exacerbation. Although the exact timing and mechanism of cortical destruction cannot be established from a single case without interval imaging, the findings emphasize that previously obtained CBCT images may not fully represent the surgical anatomy following an acute flare-up. Clinicians should therefore consider the possibility of altered cortical anatomy and be prepared to modify the surgical approach when acute clinical changes occur.