Experimental Study On Ectopic Prefabrication Of Vascularized Mandible Graft With Autogenous Ribs

Mandibular defect can be caused by tumor resection, inflammation and trauma, it can lead to confusion of occlusal relationship, reduced masticatory function, mandibular deviation of a series of questions, to bring greater physical and psychological burden to the patient. so in recent years for the mandibular defects has been a research hotspot, vascular and non-vascular bone transplanted to a metal substitute, reverse engineering, tissue engineering technology, can seek a simple, safe, good functional recovery, trauma repairway. Mandibular defect repair vascular and non-vascular autogenous bone graft, its main drawback is causing secondary trauma and secondary deformity. In recent years, tissue engineering has made great progress in basic and clinical research in bone defects, but the actual clinical application remains to be seen.PART ONEObjective:This study is to retrospectively evaluate the clinical data of patients with mandibular defects using autogenous iliac bone graft for contemporary mandibular reconstruction, and then to compare success rate of vascularized/non-vascularized iliac bone grafts for the reconstruction of segmental/partial mandible defect. Methods:Patients who underwent immediate mandibular reconstruction at the Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Wuhan University, between January2008and December2010were reviewed. The evaluated contents included gender, age, pathologic disorder, site and size of mandibular defect and success rate of iliac bone grafts. Results: The average length of vascularized and non-vascularized iliac bone grafts was5.9±1.2cm and5.5±1.4cm, respectively (P=0.407). The overall success rate of vascularized and non-vascularized iliac bone grafts was100%and76.2%, respectively (P<0.05). The success rate of non-vascularized iliac bone grafts used for segmental and partial mandible defect was91.7%and55.6%, respectively (P=0.055). The success rate of non-vascularized il iac bone grafts larger then5.5cm and less than5.5cm was63.6%and91.7%, respectively (P=0.311).Conclusions: Vascularized iliac bone graft is suitable for segmental and partial defects less than9cm in length of body of the mandible; Non-vascularized iliac graft remains a usable choice in mandibler reconstruction of partial defects less than5.5cm in length. PART TWOObjective:To explore a method for ectopic prefabrication of mandible with vascular pedicle. Methods:Cancellous bone blocks harvested from the dog ribs were packaged with mandible-shaped titanium mesh scaffold, and implanted into latissimus dorsi of dog with thoracodorsal artery and vein through the scaffold. After12weeks, bone formation and vascularization were evaluated by gross inspection, histological examination and immunohistochemistry. Results:Vascularized mandible with thoracodorsal artery and vein were formed and histological staining and immunohistochemisty confirmed new bone formation and vascularization. Conclusion:There is feasibility for ectopic prefabrication of vascularized mandible graft using cancellous ribs, which provide a new method for mandibular defect reconstruction.