A bioprinting printing approach to regenerate cartilage for microtia treatment
The need to search for biomaterials that can promote tissue regeneration and easy to replicate and manufacture is a major driving force for research and development in the area of reconstructive surgery and regenerative medicine. It is of great importance to otolaryngologists to find alternate solutions that require harvesting large amounts of autologous cartilage in patients needing cartilage grafts. Due to its very limited self-regeneration capacity, cartilage repair and reconstruction is extremely challenging. Microtia is a congenital condition of abnormal development of the outer and/ or the middle ear and can range from mild to complete absence of the ear. Current treatment methods such as autologous, alloplastic and prosthetic reconstruction have limitations such as donor site morbidity, long-term complications and implant failure. 3D printing is an exciting solution to address the challenges of microtia and create customised implants. The ability to deposit cells and biomaterials in a controlled and precise manner, allows the fabrication of implants with complex internal architecture and functional properties not achievable through traditional manufacturing methods. Despite the ability to mimic native properties and structure of tissue, 3D printed constructs using pristine inks lack the structural integrity and adequate mechanical properties for use in vivo or handling. These requirements highlight the importance of ink development and selection, which is a continuing challenge in the bioprinting process. This review will address the current treatment options for patients with microtia and the potential of 3D bioprinting in area of auricular cartilage regeneration. In particular, the use of hybrid printing to better mimic the practical and functional requirements of an ear scaffold will be discussed.