A floating inferior alveolar neurovascular bundle in a simple bone cyst: A case report

Simple bone cysts (SBCs) are uncommon lesions that usually occur in the long bones of the skeleton and in the body of the mandible. Displacement of the mandibular canal due to cystic lesions have been reported previously. However, there have been no reports in which endoscopy has been utilized to observe an inferior alveolar neurovascular bundle in the lesion lumen. This current study presents a case of mandibular SBC accompanied by a floating inferior alveolar neurovascular bundle. A 13-year-old boy presented to the Department of Dentistry and Oral Surgery, University of Fukui in March 2017 with a painless swelling in the right buccal region. He was treated with fenestration surgery using the tooth extraction socket of the right mandibular third molar. An endoscopic view of the lesion lumen presented a surrounding cortical bone without an epithelial lining and the floating inferior alveolar neurovascular bundle that was consistent with the linear low signal area of the preoperative T2-weighted magnetic resonance imaging. SBC often develops in young people, and as such is minimal surgical invasion is preferable. The current case indicated that clinicians should consider the possibility of the floating inferior alveolar neurovascular bundle in the lesion and should not damage the neurovascular bundle in the narrow surgical field.