Introduction: Root perforations may negatively affect endodontic treatment outcome if not managed properly. This case report describes successful non-surgical endodontic management of a maxillary first molar diagnosed to have iatrogenic root perforation using a calcium-silicate based root repair material. Body: A 38-year-old female patient presented with a mild pain on biting related to maxillary left first molar. Pre-operative radiograph revealed previous endodontic treatment with a missed mesiobuccal canal having an ill-defined periapical radiolucency. The patient was scheduled for non-surgical endodontic retreatment. Gutta-percha removal was done using M-pro rotary files and hand H-files. During negotiation of the mesiobuccal canal, a lateral perforation was detected in the middle third. Upon cone beam computed tomography (CBCT) examination, a separated instrument was observed in mesiobuccal canal at the level of the perforation. The original pathway of the canal was re-established using precurved manual k-files under high magnification. All canals were prepared using E-flex rotary NiTi files with 2.5% NaOCl irrigation. The perforation was sealed during obturation using a calcium-silicate based root repair material. At 3-month follow-up, the patient was asymptomatic with evidence of periapical lesion healing. Conclusion: The use of CBCT, and advancement in magnification, illumination, rotary instrumentation and disinfection played great role in lateral mid-root perforation management. Calcium-silicate based cements as a perforation repair material showed favorable clinical and radiographic outcome.