12. How do you treat an edentulous patient with a mandible fracture?
Answer:
Edentulous patients with mandibular fractures pose difficulties in management because they have no teeth to anchor the wires for MMF, the alveolar ridge is usually atrophic so that muscle pull more easily displaces fracture fragments, and the bone is mostly cortical with little capacity for repair. Fixation using dentures is often inadequate because applying enough pressure to stabilize the bony fragments usually means necrosis of the soft tissue between the denture and the alveolus.
While no uniform approach exists in treating these patients, ORIF is now generally considered the best means of management. A review by Bruce and Ellis (J Oral Maxillofacial Surg 1993; 51:904) of 167 fractures treated by several surgeons using a variety of techniques found that while 15% of patients overall had problems with union (compared with 1-4% in all mandibular fractures), 25% of those treated by closed reduction techniques had difficulty in achieving complete healing. They advocate rigid internal fixation because it eliminates the need for splints and is associated with decreased morbidity, improved healing, shorter disability time, and better jaw function and esthetics. Either compression or non-compression plates may be used.
Luhr (J Oral Maxillofacial Surg 1996; 54:250) categorized mandibular atrophy into three classes based on vertical height at the midpoint of the mandibular body:
Class I: 16-20 mm
Class II: 11-15 mm
Class III: <10 mm
A point of debate is whether to place the plate sub- or supra-periosteally. Bruce and Ellis feel subperiosteal placement maintains better rigidity and stability while minimizing necrosis of the periosteum while Luhr feels supraperiosteal placement optimizes vascularity by minimizing periosteal degloving especially in Class III patients.