Tissue Engineering for Transoral Reconstruction of Large Mandibular Continuity Defects

Reconstruction of maxillomandibular defects is met with unique challenges due to the polymicrobial environment of the oral cavity and poor native tissue regenerative potential. The lack of dynamic stimulation and functional use and the resorption rate of these defects without immediate tissue preservation or augmentation can accelerate as early as the first year after surgery. Autogenous bone graft is the material of choice in maxillofacial reconstruction, although it is extremely vulnerable to intraoral bacterial contamination. Furthermore, a donor harvest site for autogenous graft increases complication rate and hospitalization cost and often requires staged surgical approach. Due to the combination of infection risks to the recipient bed and the limited availability of autogenous donor sites and morbidity associated with the harvesting, traditional autogenous grafting is limited to staging the surgery into two parts. The first stage is the creation of the surgical defect with adequate healing time, followed by the second stage which applies the use of a transcervical approach to bone graft to allow for an isolated recipient bed from the oral cavity. The advancement of tissue engineering has allowed surgeons to offer patients alternative reconstructive options, with excellent, evidence-based outcomes compared to the gold standard set by autogenous bone grafting. In this chapter, we will explore how tissue engineering using bone marrow aspirate concentrate (BMAC), recombinant human morphogenic protein (rhBMP-2), and allogenic bone graft fulfills the three basic principles of osteoregeneration and its application in immediate, one-staged surgery with a transoral approach.