Multidisciplinary Treatment for a Young Patient With Severe Maxillofacial Trauma From a Snowmobile Accident: A Case Report

Patients involved in motor vehicle accidents often sustain both intracranial and extracranial injuries. These injuries often include significant brain injury as well as loss of both hard and soft tissues of the facial skeleton and supporting structures, reducing potential prosthesis support required of bone and skin grafting.1,2 The placement of osseointegrated implants offers an opportunity to enhance the prosthetic support with different restorative designs.3 Fixed implant-supported prostheses have numerous advantages, including improved retention, stability, esthetics, patient satisfaction, and the preservation of existing hard and soft tissues.4 

This clinical report describes the oral rehabilitation of a patient with multiple mid-face and mandibular fractures and extensive loss of the dentoalveolar segments in both the anterior mandible and maxilla as a result of a snowmobile accident. The prosthetic rehabilitation was completed by fabricating the maxillary and mandibular fixed implant-supported prostheses.

A 15-year-old boy was transferred from an outlying hospital to Massachusetts General Hospital after being involved in a snowmobile accident. His maxillofacial injuries included a comminuted LeFort I mid-face fracture with midline split, left zygomatic fracture, displaced fractured left body of the mandible, and bilateral comminuted condylar head fractures. Also, teeth numbers 5 to 10 in the maxilla and 21 to 26 in the mandible avulsed with significant loss of both the maxillary and mandibular alveolar bone (Figure 1). Under general anesthesia, open reduction and rigid internal fixation of the comminuted LeFort I mid-face fracture, left zygomatic fracture, and displaced fractured left body of the mandible were performed (Figure 2). Both of the fractured mandibular condyles were treated by closed reduction and arch bars with intermaxillary fixation. After a 10-day period, fixation was released and the patient allowed functioning under elastic rubber band guidance. An interim maxillary and mandibular removable prosthesis was placed after sufficient soft tissue healing. After approximately 8 months, evaluation of 3-dimensional CT images revealed extensive loss of alveolar bone in both the maxilla and mandible. Partial edentulism Class IV was diagnosed according to the Prosthodontic Diagnostic Index.5 To reconstruct the anterior maxilla and mandible, a corticocancellous graft was harvested from the right anterior iliac crest and bone grafted to the prepared recipient sites in the maxilla and mandible and allowed to heal for 4 months. A collagen resorbable membrane used commonly in smaller bony defects was not utilized because the graft was an autogenous corticocancellous graft, and excellent primary closure of the wound was achieved. Prior to the implant surgery, growth analysis was performed using the hand-wrist film method, and it was concluded that the patient had reached maturational growth. Based on diagnostic wax-up, the prosthesis designs were determined and the implant surgical guides in the maxilla and mandible were fabricated. A total of 10 implants (Replace Select, Nobel Biocare, Goteborg, Sweden), 13 mm in length and 3.5 and 4.3 mm in diameter, were placed in the maxilla and in the mandible approximately 6 months following placement of the bone grafts using a 2-stage surgical approach. A bony defect was noticed mesial to number 11 and grafted with autogenous and bovine bone chips. The second stage surgery to uncover the implant was performed 4 months after implant placement (Figure 3).

After the soft tissue matured, impressions were made for the maxillary and mandibular fixed implant-supported prostheses using a polyether impression material (Impregum, 3M ESPE, St Paul, Minn). The fixed-provisional interim prostheses in the maxilla and mandible were fabricated according to the previously done diagnostic wax-up to evaluate esthetics, phonetics, and occlusion. The screw-retained implant-supported fixed ceramo-metal restorations were fabricated using the Cresco precision method (Astra Tech Dental, Waltham, Mass) 2 months after the patient had the provisional prostheses (Figures 4 and 5). Also, the shape of the left maxillary canine was esthetically modified with enameloplasty and a composite resin restoration (Filtek Supreme Plus Universal Restorative, 3M ESPE) to resemble a maxillary lateral incisor.

A follow-up evaluation was performed 1 year after the delivery of the final prostheses. Implant stability was assessed manually and demonstrated excellent stability, and the attached gingiva around the implants showed no signs of inflammation (Figure 6). Radiographs revealed stable bone levels around the implants (Figure 7). The level of the attached gingiva around tooth number 11, although compromised, appeared to be stable and will be monitored continuously.

In patients with severe oral and maxillofacial trauma, the loss of the alveolus and teeth results in both esthetic and functional deformities. Immediate and comprehensive treatment involving multiple disciplines is needed to successfully restore the damaged hard and soft tissues, restore the function and esthetics, and allow the patient to regain their self esteem. It has been reported that success rates of implants placed in grafted areas are lower than implants in nongrafted sites; therefore, it was decided to replace tooth for tooth with osseointegrated implants so that in the event of a failure, the restorative phase could still be completed.6 Growth analysis is also mandatory in the teenage patient to determine the long-term success of dental implant therapy.7 

We thank Ira N. Dickerman, CDT for fabricating the final maxillary and mandibular prostheses.