Clinical and Radiographic Features of Mandibular Third Molar Gemination: A Case Report and Literature Review.

Abstract

Introduction: Gemination and fusion are rare developmental anomalies that can present significant diagnostic challenges. Due to the complexity of distinguishing between these conditions, the term "double tooth" is commonly employed in clinical practice. The precise etiology of these anomalies remains uncertain, and their occurrence in permanent dentition-particularly involving molars-is exceptionally rare. This report describes an uncommon case of gemination affecting the mandibular left third molar (tooth 3.8) and provides a comprehensive discussion contextualized within existing literature. The case report was prepared following the CARE guidelines to ensure methodological rigor and completeness. Methods: After an intraoral examination and radiographic assessment-including orthopantomography, periapical radiographs, and cone beam computed tomography (CBCT)-the patient underwent surgical extraction. The procedure involved administering a truncal nerve block to anesthetize the inferior alveolar and lingual nerves, supplemented by local infiltration anesthesia of the buccal nerve. A full-thickness mucoperiosteal flap was elevated, followed by ostectomy and odontotomy to facilitate extraction. The tooth was subsequently removed using a combination of elevators and forceps. Results: Postoperative evaluations conducted at 1.5 and 3 months confirmed complete healing of the surgical site. A detailed analysis of pre- and postoperative radiographic and clinical findings validated the diagnosis of gemination, characterized by coronal continuity with a single root and root canal. Conclusions: Gemination of third molars is exceedingly rare, with only a few cases documented in the literature. To the best of our knowledge, this is the first reported instance of gemination involving the mandibular left third molar (tooth 3.8). This report contributes to the growing body of knowledge on developmental dental anomalies and highlights the importance of thorough differential diagnosis in similar clinical scenarios.