Fused tooth: clinical approach to endodontic treatment.

Tooth fusion, the union of 2 developing dental germs, can affect the primary and permanent dentitions as well as supernumerary teeth. The anatomy of fused teeth represents a challenge when endodontic treatment is needed. This case report describes the endodontic treatment performed in a permanent maxillary incisor fused to a supernumerary tooth. A 10-year-old girl was referred for endodontic treatment in her maxillary left central incisor, which displayed a wide and bifid crown. Periapical radiographs showed that the tooth had 2 crowns with fused roots; the pulp chambers of the crowns communicated with each other at the cervical third of the tooth. Local anesthetic was administered, and a rubber dam was used to isolate the tooth. The clinician then completed preparation of the access cavity and examined the root canals of the fused teeth. After chemical-mechanical instrumentation, the clinician obturated the root canals using Tagger's hybrid technique. The pulp chamber was sealed with glass ionomer cement, and the patient was referred for restorative treatment. Teeth with morphologic abnormalities must be treated with a multidisciplinary approach to ensure a better prognosis.