Composite Mandibulectomy: A Novel Animal Model

Abstract

Objectives-Segmental mandibular defects can result after the treatment of various pathologic processes, including osteoradionecrosis, tumor resection, or fracture nonunion with sequestration. The variety of etiologies and the frequency of occurrence make the reconstruction of segmental mandibular defects a topic of significant interest. Despite these incentives, a well-established small-animal model of the segmental mandibulectomy, including composite resection, does not exist. The objective of this study is the creation of a reliable animal model that can be used to study the reconstruction of en bloc mandibular defects. Surgical techniques and an array of reconstructive options are described. Study design-Description of an animal model.Setting-Animal laboratory at a quaternary care university medical center.Methods-We present an Animal Research Oversight Committee-approved prospective analysis of survival operations in the rat model. A detailed, stepwise description of surgical technique and relevant intraoperative anatomy is presented. Postoperative management, early pitfalls, surgical complications, and future applications are discussed.Results-A total of 72 operations were performed by a single individual between July and October 2010. Two intraoperative and 9 postoperative complications were recognized. There were 6 orocutaneous fistulas, 2 abscesses, and 1 seroma. There were 4 fatalities, which were attributed to anesthetic complications (2, intraoperative), hematoma formation (1, postoperative), and foreign-body aspiration (1, postoperative).

Adipose-Derived Stem Cells and BMP-2 Delivery in Chitosan-Based 3D Constructs to Enhance Bone Regeneration in a Rat Mandibular Defect Model

“…35,36 Recently, our lab established a nonhealing critical-size marginal mandibular defect in a rat model. 1,3 The model created in present study represents clinically relevant mandibular defects often created in tumor ablation surgery. We chose this small animal model for its positive financial benefits and ethical implications.…”

“…The critical-size mandible defect (5 • 5 mm) in athymic nude rats was created according to procedures as previously described. 1 All animals received general anesthesia by inhalational of isoflurane. After hairs on the ventral surface of mandible were shaved, the animals were then prepped and draped according to a sterile manner.…”

“…S egmental mandibular defects often result from trauma, infection, dysfunction skeletal development, or secondary treatment of various pathologies such as tumor resection, and severely affect oral functions such as eating and communicating. 1,2 The primary reconstructive repair for mandibular defects requires a free vascularized bone graft. However, this approach requires lengthy surgeries carrying high rates of perioperative complications, such as donor site morbidity.…”

“…25 Furthermore, we have successfully established a novel small animal-model with a mandibular critical-sized defect (CSD) that will not heal spontaneously. 1,3 In the present study, we evaluated bone regeneration in a rat mandibular CSD model using 3D CH/CS scaffolds in combination with noggin-suppressed ASCs and BMP-2. Noggin was downregulated in ASCs by transducing lentivirus particles with short hairpin RNA (shRNA) targeting noggin (ASCs Nog -).…”

Polylactic Acid Based Nanocomposites: Promising Safe and Biodegradable Materials in Biomedical Field

“…Now the reconstruction of bone has been a major focus point in preclinical research and clinical application, giving rise to the development of materials that help to regenerate bone and repair bone defects [41][42][43]. Bone defect repair is really common in orthopedic surgeon [44], where synthetic bone substitutes must be used and implanted in human bodies and it is of great importance to find suitable substitutes.…”