Does mandibular osteotomy affect the infraorbital nerve? a prospective study.

Objectives: The aim of this study was to evaluate the sensory function of the infraorbital nerve after orthognathic surgery (OS).

Materials And Methods: Patients who underwent Le Fort I osteotomy with or without BSSO for dentofacial deformity treatment were studied. Two groups were created according to whether BSSO was performed. Class A tests were performed to determine the degree of peripheral nerve damage. The Class B test was performed if decreased sensation was detected in at least one of these tests. A Class C test was performed if abnormal sensation was detected.

Results: Twenty-eight patients (n=56) who underwent OS were included in this prospective study. Of the patients, 57.1% were female, 42.9% were male, and the mean age was 24.6 (±3.8). Seven patients were in group 1 (n=14), and 21 patients were in group 2 (n=42). In both groups, there were statistically significant differences between T1 and T2 (p<0.001), and the mean NSD score at T2 was higher than that at T1. The mean NSD score in the single jaw group was higher than that in the double jaw group at all time points.

Conclusions: Bimaxillary surgeries had a negative effect on the somatosensory changes that developed in the early period. The upper lip's somatosensorial recovery was faster than IOR and single jaw recovery was faster than double jaw.

Clinical Relevance: Maxillofacial surgeons performing orthognathic surgery should be aware that in double jaw operations, changes in the somatosensory function of the ION are more severe.