Risk factors affecting somatosensory function after sagittal split osteotomy.

PURPOSE: The aim of this study was to evaluate potential individual and intraoperative risk factors associated with bilateral sagittal split osteotomy (BSSO) and to correlate the findings with postoperative changes in somatosensory function.

PATIENTS AND

METHODS

A total of 18 men and 29 women (mean age, 31 +/- 10 years) scheduled for BSSO participated in 1 session before BSSO and 5 sessions after BSSO (at 2 and 14 days and 3, 6, and 12 months). At each session, subjective oral sensation was scored and quantitative sensory tests were performed.

RESULTS

The results showed that complete exposure and free dissection of the inferior alveolar nerve during BSSO increased self-reported changes in lower lip sensation and lower lip tactile threshold after BSSO (P < .01). Long surgical movements reduced self-perceived jaw-opening function and impaired 2-point discrimination (P < .05). Significant correlations were noted between preoperative values for somatosensory function and changes in these variables after BSSO. Patients with low sensory thresholds before BSSO experienced more impairment than those patients with higher preoperative sensory thresholds.

CONCLUSION

These findings imply that somatosensory function after BSSO is dependent on both intraoperative risk factors and preoperative sensation levels.