Long-lasting neurosensory disturbance following advancement of the retrognathic mandible: distraction osteogenesis versus bilateral sagittal split osteotomy

Neurosensory disturbance (NSD) of the inferior alveolar nerve (IAN) is the most common complication after bilateral sagittal split osteotomy (BSSO) and distraction osteogenesis (DO) of the retrognathic mandible. It is suggested that the risk is lower after DO than after BSSO. This retrospective study compared both techniques with regard to long-lasting NSD and overall patient satisfaction. 91 patients (representing 182 IANs) were included, they completed a questionnaire and underwent an objective neurosensory test. In the BSSO-group (90 nerves), long-lasting NSD was reported in 27 cases (30%) versus 21 cases (23%) in the DO group (92 nerves). In 39 cases (24 BSSO, 15 DO) the long-lasting NSD was reported in the lower lip, the chin or both. Of these cases, 9 (5 BSSO, 4 DO) were objectively tested positive. The overall prevalence was 8% in the BSSO group and 10% in the DO group. There was no significant difference in subjectively reported and objectively measured NSD between the groups. In this study patients seemed to over-report the NSD compared with the objective findings. For both procedures, overall patient satisfaction was high.