M. F. Griffin1,2, D. Kalaskar1, A. Seifalian1, P. Butler1,2 1University College London,Surgery,London, UK, United Kingdom 2Royal Free Hospital,Plastic Surgery,London, , United Kingdom
Introduction: Current surgical reconstruction of auricular defects involves harvesting rib cartilage and carving a new cartilaginous framework. However, this ‘gold standard’ technique causes pain, donor site morbidity and is restricted by cartilage availability. The use of alternative synthetic materials is also limited due to the complications relating to poor tissue integration and angiogenesis, leading to extrusion and infection. We aim to meet this clinical challenge by creating a new material for auricular reconstruction using a novel nanocomposite polymer called polyhedral oligomeric silsesquioxane poly(carbonate urea) urethane (POSS-PCU), which has already been successfully taken to the clinical benchside as a replacement trachea, tear duct and vascular by-pass graft.
Method: The chemical, structural and mechanical properties of POSS-PCU has been optimised and characterized to ensure it is suitable for auricular reconstruction. The biocompatibility of POSS-PCU has been tested with several human cell lines and levels of angiogenesis, tissue integration and immune response has been explored using in vivo animal models.
Result: POSS-PCU was found to support cell adhesion, proliferation and extracellular matrix formation of human dermal fibroblasts, endothelial cells, chondrocytes and adipose stem cells, using QT-PCR and immunocytochemistry. The subcutaneous implantation of POSS-PCU in rodent models demonstrated good tissue integration and vessel formation over 3 months without infection and extrusion.
Conclusion: POSS-PCU has shown to be a promising material for auricular reconstruction. Preclinical testing will be completed in the near future prior to embarking on a UK multicenter clinical trial.