Faculty Bibliography

BACKGROUND: : Tumors of the mandible are complex, often requiring replacement of bone, soft tissue, and teeth. The fibula flap has become a routine procedure in large tumors of the jaw, providing bone and soft tissue at the time of the resection. In current practice, dental reconstruction is delayed for 3 to 6 months, leaving the patient without teeth in the interim. This can be disfiguring and anxiety provoking for the patient. METHODS: : In this article, the authors present three patients with benign tumors of the mandible who underwent virtually guided resection, fibula reconstruction, and insertion of an implant-retained dental prosthesis in one operation. In addition, the authors report their early experience using this technique in the maxilla. RESULTS: : The authors present a case series of three patients with benign mandibular tumors and one patient with a benign maxillary tumor who underwent total reconstruction using computer-aided design and computer-aided manufacturing technology in a single stage. CONCLUSIONS: : In the right situation, total mandibular reconstruction is possible in a single stage. This is demonstrated by the successful outcomes of these patients. CLINICAL QUESTION/LEVEL OF EVIDENCE: : Therapeutic, V.

Background The authors describe our current practice of computer-aided virtual planned and pre-executed surgeries using microvascular free tissue transfer with immediate placement of implants and dental prosthetics.Methods All patients with ameloblastomas treated at New York University (NYU) Medical Center during a 10-year period from September 2001 to December 2011 were identified. Of the 38 (36 mandible/2 maxilla) patients that were treated in this time period, 20 were identified with advanced disease (giant ameloblastoma) requiring aggressive resection. Reconstruction of the resultant defects utilized microvascular free tissue transfer with an osseocutaneous fibular flap in all 20 of these patients.Results Of the patients reconstructed with free vascularized tissue transfer, 35% (7/20) developed complications. There were two complete flap failures with consequent contralateral fibula flap placement. Sixteen patients to date have undergone placement of endosteal implants for complete dental rehabilitation, nine of which received immediate placement of the implants at the time of the free flap reconstruction. The three most recent patients received immediate placement of dental implants at the time of microvascular free tissue transfer as well as concurrent placement of dental prosthesis.Conclusions To our knowledge, this patient cohort represents the largest series of comprehensive computer aided free-flap reconstruction with dental restoration for giant type ameloblastoma.

Craniofacial vascularized composite allotransplantation is especially challenging when bony components are required. Matching the complex three-dimensional anatomy of the donor and recipient craniofacial skeletons to optimize bony contact and dental occlusion is a time-consuming step in the operating room. Currently, few tools exist to facilitate this process. The authors describe the development of a virtual planning protocol and patient-specific device design to efficiently match the donor and recipient skeletal elements in craniofacial vascularized composite allotransplantation. The protocol was validated in a cadaveric transplant. This innovative planning method allows a "snap-fit" reconstruction using custom surgical guides while maintaining facial height and width and functional occlusion. Postoperative overlay technology in the virtual environment provides an objective outcome analysis.

Classic tissue engineering paradigms are limited by the incorporation of a functional vasculature and a reliable means for reimplantation into the host circulation. We have developed a novel approach to overcome these obstacles using autologous explanted microcirculatory beds (EMBs) as bioscaffolds for engineering complex three-dimensional constructs. In this study, EMBs consisting of an afferent artery, capillary beds, efferent vein, and surrounding parenchymal tissue are explanted and maintained for 24 h ex vivo in a bioreactor that preserves EMB viability and function. Given the rapidly advancing field of stem cell biology, EMBs were subsequently seeded with three distinct stem cell populations, multipotent adult progenitor cells (MAPCs), and bone marrow and adipose tissue-derived mesenchymal stem cells (MSCs). We demonstrate MAPCs, as well as MSCs, are able to egress from the microcirculation into the parenchymal space, forming proliferative clusters. Likewise, human adipose tissue-derived MSCs were also found to egress from the vasculature and seed into the EMBs, suggesting feasibility of this technology for clinical applications. We further demonstrate that MSCs can be transfected to express a luciferase protein and continue to remain viable and maintain luciferase expression in vivo. By using the vascular network of EMBs, EMBs can be perfused ex vivo and seeded with stem cells, which can potentially be directed to differentiate into neo-organs or transfected to replace failing organs and deficient proteins