Assessing the incidence of nerve injuries according to different mandibular osteotomies including Wing osteotomies.

We use currently 3 types of new mandibular osteotomies (a shortened Bilateral Sagittal Split Osteotomy (BSSO), associated or not with Chin Wing or Mini Wing). Chin osteotomy is a modified genioplasty extended along the basilar border and the angles of the mandible. These osteotomies are associated with a risk of inferior alveolar nerve (IAN) damage. We prospectively studied 113 consecutive patients operated on by the same surgeon who underwent one of the following procedures: (1) isolated BSSO, (2) BSSO with a Chin Wing, (3) BSSO with a Mini Wing, (4) isolated Chin Wing. We analyzed rates of IAN damage and impact on the patients' life by using a subjective questionnaire administered at the patient's 1 year follow up appointment between June 2018 and August 2019. Sixty-seven patients underwent isolated BSSO, 24 BSSO with Mini Wing, 13 BSSO with Chin Wing, and 9 Chin Wing only. Our analysis reveals that nerve damage is greater in the BSSO group associated with Chin Wing (50% vs. 21.6%; p=0.006). However, there is no significant difference between nerve damage in the Mini wing group and the isolated BSSO group (27.1% vs. 21.6%; p=0.432). In the isolated Chin Wing group, the inferior alveolar nerve damage rate was 11%. There is no significant difference between the groups with regard to the impact of the nerve damage on the patients' life. In case of BSSO with concomitant Wing osteotomy, we conclude that Mini Wing osteotomies cause less nerve related morbidity than Chin Wing.