Short-Term Sensory Impairment after Orthognathic Surgery

Abstract

Summary • Subjective reports of abnormal sensations, pinprick sensitivity, and two point sensitivity were assessed in 158 orthognathic surgery patients before and 6 weeks after bilateral sagittal split and!or Le Fort I osteotomies in a controlled clinical trial involving two centers: a private practice in Seattle and a university teaching hospital in Chapel Hill (UNC). • The presurgical findings for sharpness and for two point perception were similar at the two centers and consistent with published findings for nonsurgery subjects. A new finding at both centers was that patients 25 years of age or older were more sensitive to pinprick than patients younger than 25 years of age. • Six weeks after surgery, a high percentage (approximately 90%) of patients reported abnormal sensations. The altered sensations were limited largely to facial sites innervated by nerves in close proximity to the surgical osteotomies. Pinprick sensitivity and two point sensitivity (to a lesser degree) were impaired at these same locations. • For patients who underwent a combined (two-jaw) procedure, neurosensory function was impaired to a greater extent on the lower face than on the midface 6 weeks after surgery. Unexpected was the finding that impairment on the midface of these patients may have been less than that of patients who underwent maxillary surgery only. • The postsurgery findings were similar at the two centers and for the two sides of the face, which indicates that the risks of neurosensory impairment did not differ from any hypothetical difference in the execution of surgical skills between centers or sides. • The addition of a genioplasty procedure resulted in greater sensory loss than that associated with the osteotomies, which indicates that greater impairment occurred when multiple procedures were performed. • There was a trend for the additional loss after genioplasty to be greater for patients younger than 25 years of age than for patients 25 years of age or older. Further consideration of age and gender did not explain variation in the patients' impairment beyond that accounted for by the type of surgery and presence versus absence of genioplasty. • The association of patients' reports of abnormal sensations with loss in pinprick sensitivity was stronger than the association with loss in two point perception, which attests to the usefulness of pinprick sensitivity in assessing sensory impairment clinically. • Additional work is needed to understand better the pattern of sensory recovery after different orthognathic surgery procedures, to clarify better the affect of age and gender on neurosensory outcome measures, and to reconcile differences in the literature regarding these issues. Clinical trials also are needed to address the role of patients' psychologic well-being and attitude of the perception of altered sensations in their overall recovery and satisfaction and to evaluate the effectiveness of noninvasive therapies that may assist patients in coping with altered sensations.