The most severe maxillofacial battle injured (BI) can be further complicated by composite tissue avulsions and burns (77% of evacuated burn casualties involve the face). Burns occur with higher frequency due to the nature of modern weapons, and they occur in combination with other injuries.
Burned service members (SM) commit years after their initial injury to multiple operations, significantly delaying their return to function. Research and development of new strategies to reduce hypertrophic scar formation and contractures following deep burns is being intensively pursued at DTRD.
The mouse burn model is used to select agents, devices, and strategies effective in reducing scar contractures. Promising technologies will then be transferred to the pig model.The pig is a favorable burn model for human skin for several reasons: 1) The composition is similar and epidermal turnover occurs in both species at similar rates; 2) Due to its size, the pig is of sufficient size to create multiple wounds, which allows comparison of several treatments with controls in the same animal. Additionally, pig skin is considered to be most closely related to humans.
A porcine model of a burn contact wound is currently underway to investigate strategies for improving the durability of the dermis, the dermal contribution is directly investigated by varying its thickness. The payoff of this proposed study is to obtain and transfer the highest quality and most durable skin early after burn debridement, resulting in improved clinical outcomes. The knowledge gained from this work will likely contribute to the next phase of this program— investigating the contribution of the hypodermis.
Scars, deformities, and loss of function are the usual outcome of these severe facial burns or wounds despite multiple procedures and application of advanced conventional technologies.
In skin and soft tissue wounds, severe cases of hypertrophic scars can result in disfigurement, restriction of motion, and disabling pain. We are studying the pathophysiology underlying hypertrophic scar formation and regulation of the fibrotic response using a rabbit hypertrophic scar model and investigating biological therapies comprised of cells, matrices, growth factors and other small molecules that will provide the environment necessary for scar reduction and proper wound healing.
To that end, projects in this area address: 1) the potential wound-healing capabilities and scar-free healing of mesenchymal stem cells (MSCs); 2) in collaboration with Dr. Robert Christi’s group, the potential of a composite, composed of adipose-derived stem cells (ASCs) in a PEG-fibrin gel, to improve scar compliance; and 3) lipid mediators to resolve inflammation for scar reduction.
In parallel with discovery of effective agents to reduce scarring will be the development of a custom automated face dressing for treatment of face burns. The device aims to cover and protect the open face wound after debridement of deep burns, provide a moist sealed wound environment, evacuate effluents through negative pressure wound therapy, deliver agents and fluids to reduce excessive inflammation, and, finally, act as a platform to close wounds through sequential application of biomaterials and tissue grafts in a controlled manner.