Incidental Finding of a Supernumerary Tooth Fused to a Mandibular Second Molar Using Cone Beam Computed Tomography (CBCT): A Case Report

Document Type : Case Reports


1 Student Research Committee, Babol University of Medical Sciences, Babol, Iran

2 Department of Oral and Maxillofacial Radiology, Dental Faculty, Tehran University of Medical Sciences, Tehran, Iran

3 Department of Oral and Maxillofacial Radiology, Dental Faculty, Babol University of Medical Sciences, Babol, Iran


The twinned tooth is a rare phenomenon among dental anomalies, which may develop during the bud stage tooth morph differentiation. Twinned tooth refers to the fusion of two adjacent tooth buds or gemination of the single bud. Clinically it is difficult to differentiate between fusion and gemination. During this anomaly, primary dentition is mostly affected rather than permanent dentition, and predominantly, it is observed unilaterally. Gemination is more common in the anterior region of maxilla, while fusion mainly occurs in the anterior mandibular region. There is no definite etiology for these anomalies reported, but genetic and environmental factors are mostly mentioned as potential risk factors. This paper describes a case of fusion of the second mandibular molar with a supernumerary tooth. Twinned teeth can cause clinical problems such as dental caries, periodontal, and aesthetic problems. Early diagnosis can be achieved through careful clinical and radiographic examinations; however, in most cases of twinned teeth, no significant clinical problem is reported.


Main Subjects

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