The authors aimed to present dental treatment of the cadaveric tooth in a transplanted maxilla in a patient with facial transplantation with bony framework and soft tissue envelope. The treatment procedure was scheduled after physical examination, and the final plan was designed according to the patient's special medical condition. The authors reported the first successful endodontic treatment of an allogeneic cadaveric donor tooth in a patient with facial transplantation. Dental disease represents a potential risk for infection in patients with allogeneic transplantation, which could affect the success of tissue transplantation and might lead to life-threatening conditions. The (re)treatment of the diseased teeth is possible even after the transplantation. The health of the teeth and jaws of the donor should be evaluated before transplantation, especially when maxilla or mandible transplantation is planned.