Simultaneous innervated and vascularized iliac bone flap for reconstructing mandible and nerve defects

Abstract

The functional reconstruction of large maxillofacial defects is a major issue in oral and maxillofacial surgery, and autologous bone transplantation is the main method. However, bone is readily absorbed following an autologous bone transplant. Even with vascular anastomosis, spontaneous osteoporosis of transplanted bone is still serious, which affects dental implantation and functional recovery. Therefore, osteoporosis of the grafted bone has become one of the main complications of jaw reconstruction, and there is no preventive measure. The problem that autologous bone with sufficient blood supply cannot avoid osteoporosis suggests that systemic factors such as nerves, which have been neglected in traditional methods, may regulate the internal environment of the transplanted bone. Based on previous studies on the regulation of mesenchymal stem cells by the neural microenvironment, we initiated a new surgical procedure for innervated and vascularized iliac bone flaps based on animal model and cadaver studies. In the innervated and vascularized iliac bone flap, vascular microanastomosis was performed in conjunction with microneuronal anastomosis between the simultaneously harvested ilioinguinal nerve (which innervates the iliac bone and is usually sacrificed and neglected in the conventional vascularized iliac bone flap) and the inferior alveolar nerve proximally and with the mental nerve distally. By conducting clinical retrospective studies and prospective randomized controlled trials, we proved that the novel method of simultaneous innervated iliac bone transplantation can not only prevent bone resorption but also restore the sensation of adjacent soft tissues such as the lip. This may solve the key problems of sensory loss and osteoporosis after mandibular reconstruction, ensure the success of dental implant dentures, and put forward the new concept of "blood supply + innervation" bi-system bone transplantation.

Keywords

• mandible defect ，
• mandibular reconstruction ，
• free iliac bone flap ，
• vascularization ，
• deep circumflex iliac artery and vein ，
• ilioinguinal nerve，
• mandibular nerve，
• mental nerve，
• innervation，
• osteoporosis ，
• sensation，