Sensory disturbances associated with rigid internal fixation of mandibular fractures.

Sensory status of the inferior alveolar nerve was monitored in 133 patients with 150 fractures in the region of the mandibular canal treated with rigid internal fixation preoperatively and 6 weeks postoperatively. Eighty-five of the patients were reevaluated on final follow-up at an average of 15.9 months. Preoperative sensory disturbance (58.5%) correlated significantly only with the presence of fracture displacement. The occurrence of postoperative paresthesia (76.0% at 6.2 weeks, 46.6% at 15.9 months) correlated significantly with the degree of mandibular edentulousness. Patients with edentulous mandibles, especially when a compression plate was used, suffered significantly more often from nerve injury than fully dentate patients. The results indicated that the sensory disturbance was caused by the surgical procedure. In contrast to previous assumptions, displacement of the fracture and preoperative sensory status did not correlate with postoperative occurrence of paresthesia.