Inferior alveolar nerve function after mandibular osteotomies

A total of 1034 patients who had undergone orthognathic surgery were examin ed after 2 years; 818 had been treated with varying types of mandibular ost eotomy such as vertical ramus osteotomy, sagittal split ramus osteotomy, an d genioplasty. Neurosensory function in the mental nerve region was assesse d by evaluating light touch perception. The incidence of neurosensory deficiency was 216/548 (39%) after sagittal s plit ramus osteotomy, 26/140 (19%) after extraoral vertical ramus osteotomy , 9/78 (12%) after genioplasty and 60/650 (9%) after intraoral vertical ram us osteotomy. Additional genioplasty increased both the incidence and sever ity of neurosensory disturbance after intraoral vertical ramus osteotomy bu t did not significantly influence the neurosensory function after sagittal split ramus osteotomy. The incidences of neurosensory disturbance after mandibular osteotomies in this report correspond well with those previously reported, but the inciden ce of almost 40% after sagittal split ramus osteotomy must be considered a disquieting drawback of the procedure.