Trigeminal neuropathy after mandibular fractures: Epidemiology and neurophysiologic diagnosis

Objectives: To study the trigeminal nerve neuropathy prevalence after mandibular fractures and follow nerve recovery and to examine associations with clinical features. Subjects: The files of 304 patients treated for 424 mandibular fractures in Hadassah Medical Center between 2001 and 2008 were analyzed. Twenty-five patients with paresthesia were examined by electro-diagnostic conduction test (quantitative sensory testing). Results: The most common fracture sites were the symphysis (28.5%) and condyle (21.4%). A strong correlation between fracture severity and treatment modality was found. Nerve damage occurred in 13.4% of nondisplaced fractures and in 65.3% of >5 mm displaced fractures. Patients who were treated by open reduction internal fixation demonstrated the biggest difference in quantitative sensory testing values between the affected and nonaffected sides. C nerve fibers were the most damaged and least regenerated. There was correlation between damage perception and objective test results. Conclusions: There is a correlation between fracture type and displacement severity on neurologic deficit and prognosis. The objective neurosensory damage was manifested by higher nerve excitation threshold on the injured side. Patients should be informed on the prognosis of neurologic deficit according to fracture type.