Case History
43-year-old edentulous female patient sustained a fall after a new onset of seizures resulting in bilateral mandibular body fractures. The patient had no other injuries and was treated with anticonvulsants before being taken to the operating room.
Treatment Options
Treatment options include: 1) ORIF (open reduction internal fixation) with dynamic compression plates spanning the edentulous fracture sites using an intra-oral approach, 2) ORIF with compression plates using an extra-oral approach, or 3) ORIF using a reconstruction plate with autogenous bone grafting with an extra-oral approach.
Operative Stabilization
Initial management of this patient involved a full medical work-up to evaluate the reasons for the fall and seizure. The patient was taken to the operating room and initially the ORIF of the bilateral mandibular body fractures was then performed. An intra-oral approach was used and 2.4 mm compression plates were placed, spanning the edentulous fracture sites (Figure 1). The postoperative course was uneventful and the patient was discharged on a liquid diet and anticonvulsants. She was instructed to follow-up with her primary care physician for anticonvulsant management. She was also instructed to refrain from wearing her dentures.
Salvage Principles
At a 4-week follow up examination, the patient complained of bilateral jaw pain. The clinical examination revealed moderate mobility of the distal segment, but no evidence of infection. Radiolucencies at the fracture sites were noted on a panoramic radiograph, which were suggestive of non-union (Figure 2). These findings indicated non-union healing of the mandibular fracture sites. The patient was returned to the operating room and the dynamic compression plates were removed using an extra-oral approach. Pre-operatively, a 2.7 mm reconstruction plate was contoured to a custom acrylic mandible (Medical Modeling, Golden, CO) generated from a computer-aided tomography (CT) scan using computer aided design-computer aided machining (CAD-CAM) technology (Figure 3 and Figure 4). After removal of the compression plates the non-union fracture site was gently curreted and the custom pre-adapted reconstruction plate was fixated in place (Figure 5). The fracture sites were then grafted with cancellous bone from the iliac crest and compacted into a custom-fabricated polyglactin mesh tube (Figure 6 and Figure 7). The site was then cosmetically closed, and her post-operative course was uneventful. At the 4-week post-operative examination, the fracture sites were stable and the patient was free of pain. A panoramic radiograph was taken 12 and 36 weeks post-operatively revealing bony union of the fracture site (Figure 8).
Summary
The 2.7 mm reconstruction plate pre-operatively adapted to the custom acrylic mandible tray worked well in providing rigid fixation to the edentulous mandible fracture. The use of CAD-CAM technology for this situation minimizes the operative time required to adapt the reconstruction plate to the patient's mandibular morphology. The use of the polyglactin mesh packed with autogenous cancellous bone grafts aided in retention of the graft and healing of the nonunion fracture site. This particular technique allows for the transplantation of viable osteogenic cells and encourages increased revascularization of the graft. The polyglactin mesh is resorbed by hydrolysis within 3 to 4 months. Multiple etiologies contribute to mandibular nonunion, which is especially difficult to treat in the setting of an edentulous mandible. The desired treatment is debridement of the fracture site, rigid immobilization of the segments, and bone grafting when required. Close follow-up thereafter is important to assess viability of the graft and adequate immobilization of the fracture segments.