Complications of orthognathic surgery: the inferior alveolar nerve

This study analyzes permanent paresthetic disorders regarding the inferior alveolar nerve (IAN) after mandibular ramus sagittal osteotomy procedures. Fifty patients (ie, 100 nerves) who underwent mandibular bilateral sagittal split osteotomy between 2003 and 2007 were evaluated to detect sensorial disorders of the IAN. The evaluation was performed for each patient at least 1 year after surgical intervention. The sagittal osteotomy of the mandible ramus was performed according to Epker-Hunsuk technique. The method of fixing through titanium plates and monocortical screws and the displacement width of the osteotomized stumps were also considered. The evaluation of the IAN functionality was performed both subjectively, by means of a questionnaire, and clinically, by using 4 types of tests: light-touch sensation, pinprick sensation, Weber test, and Dellon test.The clinical test analysis revealed that no nervous lesion was detected in 52% of the tested sites, whereas 24% reported significant nervous lesions. In the subjective evaluations, 74% of the patients described the discomfort related to the neurologic alteration as "absent to mild" or "mild to moderate," 10% as "moderate to serious," and 4% as "serious."We observe that the percentage of significant nervous lesions is relatively low and that it matches the mean described in literature. The central nervous system capacity to hide or compensate for functional deficits due to peripheral nervous lesions was confirmed by the comparison between the results of the clinical tests and the patients' subjective evaluations.