It is difficult to clinically make differential diagnosis between fusion and gemination, especially when these anomalies take place together with hypodontia or supernumerary tooth. The term “double tooth” is therefore preferred by many authors. These teeth may occur due to the fusion of adjacent tooth germs, hence the term fusion. Alternatively, this anomaly may be the result of attempted division of a single tooth germ, hence the term gemination. This case report describes the management of double tooth affecting the permanent maxillary left central incisor. As a result of clinical and radiographic examinations, it was determined that this tooth consisted of fusion of central left maxillary incisor and supernumerary tooth. The double tooth was separated for having crown size of adjacent central incisor and supernumerary tooth with related root was extracted. After 1- year follow up, the maxillary left central incisor still remains vital. This case shows that a precise diagnosis is important in sectioning a double tooth, and that cone-beam computed tomography (CBCT)- based data are very useful in planning complex treatment.