A supernumerary tooth fused to the facial surface of a maxillary permanent central incisor: case report.

A case of a supernumerary tooth fused to the facial surface of a maxillary permanent central incisor is reported. Root canal therapy on the maxillary central incisor was performed due to pulpal communication between the supernumerary tooth and the maxillary central incisor after removing the supernumerary tooth structure. The communication was sealed with mineral trioxide aggregate. The difference between fusion and gemination is discussed.