2016 年 29 巻 3 号 p. 173-179
In practice, it is often difficult to perform open reduction for the treatment of mandibular fracture with temporomandibular joint (TMJ) dislocation in a totally edentulous patient when the denture is not adjusted. In this study, the application of implant simulation software and guided surgery technique for fixing the denture was attempted for the treatment of mandibular fracture with TMJ dislocation in a totally severe atrophic edentulous patient, and resulted in successful treatment.
In January 2012, an 85-year-old man complaining of mouth closing disorder was referred to our clinic, because open reduction surgery of the mandible could not be successfully treated in the plastic surgery clinic of our hospital. Three-dimensional CT imaging revealed bilateral fracture of the mandible and unilateral anterior luxation of TMJ in the severe atrophic totally edentulous maxilla and mandible. His upper and lower dentures were unstable in the oral cavity.
Open reduction and intermaxillary fixation using the patient's own dentures were planned. However, his upper denture was unstable in the oral cavity and his upper jaw had insufficient bone volume to place intermaxillary fixation (IMF) screws. Therefore, proper positons and safety spaces for IMF screw placement were examined by using implant simulation software and guided surgery procedure. CT images were taken using the so-called double scanning technique and the IMF screw positions were analyzed using the implant simulation software (SimPlant®). Prior to the operation, drill guiding holes were manually drilled in the maxillary denture according to the simulation results. The hooks for intermaxillary fixation were attached to the upper and lower dentures.
In February 2012, open reduction surgery was performed under general anesthesia. After the manipulate reduction of TMJ, the maxillary denture was rigidly fixed using five IMF screw implants 10 or 12 mm in length without perforation into the maxillary sinuses. Following the circumferential wiring of the lower denture, the intermaxillary fixation was successfully done for proper occlusion. Rigid fixation of the fractured mandibula was performed using a titanium mandibular reconstructive plate. Postoperatively, there was no evidence of TMJ redislocation.
The present case suggests that, in severe atrophic totally edentulous patients, the application of implant simulation software and guided surgery technique for fixing the denture is an effective strategy for the treatment of mandibular fracture with TMJ dislocation and the prevention of reluxation of TMJ.
