Abstract
BACKGROUND: The numbers of mandibular first premolar roots and root canals vary, and the incidence of three roots and three canals is 0.09%. CASE SUMMARY: In this article, we review the root and root canal conditions for the mandibular first premolar and report the case of a mandibular left first premolar with three roots and three canals in a male patient, with suggestions for clinical diagnosis and treatment. The patient was referred by an orthodontist for the extraction of the tooth. Preoperative cone-beam computed tomography examination revealed that it had three roots. Under local anesthesia, the extraction socket was carefully expanded, and the tooth was successfully removed intact using forceps. The procedure was uneventful, with no root fractures, postoperative bleeding, or sensory abnormality observed. CONCLUSION: The mandibular first premolar is characterized by multiple roots and canal variations that can increase the difficulty of treatment.