Effects of Synthetic Graft Versus Autograft in the Generation of Autologous Free Tissue Flaps
Mark Wong is Professor and Chairman of the Department of Oral and Maxillofacial Surgery at The University of Texas School of Dentistry at Houston, where he also serves as the Director of Residency Training. Dr. Wong is currently the President of the American Academy of Craniomaxillofacial Surgeons and the President of the International Board for the Certification of Specialists in Oral and Maxillofacial Surgery. His clinical and research interests are focused on reconstructive surgery, tissue engineering of bone and the biomechanical characterization and regeneration of the temporomandibular joint. His research is funded by the NIH and the Department of Defense. Dr. Wong has served on a number of educational and research committees for AAOMS. He is a Past President of ABOMS, President-elect of the American Academy of Craniomaxillofacial Surgeons, and currently Chairs a Steering Committee for the development of an International Board for the Certification of Specialists in Oral and Maxillofacial Surgery.
Reconstruction of large mandibular defects following blast injury or the resection of advanced pathology is particularly challenging when both bone and soft tissue is missing. Current methods to address this problem include staged reconstruction techniques delaying hard tissue reconstruction until the soft tissue bed has been restored or the use of vascularized hard and soft tissue flaps. Donor site morbidity is significant with either approach and this concern forms the basis for a new method of regenerating bone with accompanying soft tissue.
This project leverages technology and expertise developed for a project initially funded by the Armed Forces Institute of Regenerative Medicine II initiative. Using a different site in the flap recipient as an in vivo bioreactor, synthetic materials placed into chambers will be used to generate bone flaps of customizable dimensions. These flaps are allowed to vascularize before they are harvested and transferred to the recipient defect. The Osteo Science Foundation award will provide resources to study the osteogenic capabilities of different materials implanted into a validated large animal (sheep) model as well as characterize the niche environment surrounding the bone chamber by analyzing the cell population, gene expression and other tests for osteogenic activity. Additional mechanical and histomorphometric tests will determine the load-bearing characteristics of the construct as well as morphology.
While the project is focused on mandibular defects, the same strategy could be adopted for other challenging defects in the maxillofacial region.
A.M. Tatara, S.R. Shah, N. Demian, T. Ho, J. Shum, J.J.J.P. van den Beucken, J.A. Jansen, M.E. Wong, and A.G. Mikos, “Reconstruction of Large Mandibular Defects Using Autologous Tissues Generated From In Vivo Bioreactors,” Acta Biomaterialia, 45, 72-84 (2016). DOI:10.1016/j.actbio.2016.09.013 Read Abstract
AM Tatara, SR Shah, E Watson, BT Smith, N Demian, IA Hanna, JC Melville, J Shum, T Ho, JJ van den Beucken, JA Jansen, ME Wong, AG Mikos “Ovine Model For Generation of Tissue-Engineered Vascularized Bone of Large Volume and Custom Geometry” Tissue Engineering Part A (22). 2016, Dec; S155-156 Read Abstract
Alexander M. Tatara, Gerry L. Koons, Emma Watson, Trenton C.Piepergerdes, Sarita R. Shah, Brandon T. Smith, Jonathan Shum, James C.Melville, Issa A. Hanna, Nagi Demian, Tang Ho, Anthony Ratcliffe, Jeroen J. J. P. van den Beucken, John A. Jansen, Mark E. Wong, Antonios G. Mikos. Biomaterials-aided mandibular reconstruction using in vivo bioreactors. Proceedings of the National Academy of Sciences Mar 2019, 201819246; DOI:10.1073/pnas.1819246116. Full Text
A.M. Tatara, S.R. Shah, E. Watson, B.T. Smith, N. Demian, I.A. Hanna, J.C. Melville, T. Ho, J. Shum, J.J.J.P. van den Beucken, J.A. Jansen, M.E. Wong, and A.G. Mikos, “Leveraging Biomaterials for High Fidelity Mandibular Reconstruction,” Tissue Engineering and Regenerative Medicine International Society 2016 Americas Meeting, San Diego, California, December 11-14th, 2016.
A.M. Tatara, S.R. Shah, E. Watson, B.T. Smith, N. Demian, I.A. Hanna, J.C. Melville, T. Ho, J. Shum, J.J.J.P. van den Beucken, J.A. Jansen, M.E. Wong, and A.G. Mikos, “Ovine Model For Generation of Tissue-Engineered Vascularized Bone of Large Volume and Custom Geometry,” Tissue Engineering and Regenerative Medicine International Society 2016 Americas Meeting, San Diego, California, December 11-14th, 2016.