The disparity between the demand for organ transplantation and the number of available organs has long been realized. Needs such as these have led to the emergence and evolution of tissue engineering, where a wide range of disciplines including biochemistry, engineering and material science have been integrated and applied. Encompassing diverse applications, the most exciting and controversial research has centered on regenerative medicine with the repair or replacement of tissues/organs. However, while traditional techniques largely apply scaffold-based methods to constructing tissue structures, bioprinting utilizes techniques from manufacturing to the layered additive biofabrication that gives bioprinting its revolutionary edge and potential.
Past tissue engineering research attempted to fabricate "solid biodegradable scaffolds" requiring the sequential cell-specific seeding in a bioreactor. This approach strives to maintain a stable environment for cell growth, cell attachment and stimulated development of an engineered construct with the similar shape and mechanical properties to that of native tissue. However, this approach has met little success and many challenges where limitations include issues with precise cell placement and the expensive and time-intensive cultivation and tissue assembly process.
In addition, for the development of non-hallow organs, other challenges arise in providing a means of cell penetration and seeding, length of time for tissue maturation (time scale of months - not practical), difficulty in developing organs with diverse tissue composition and distribution, poor performance of biomechanical properties of engineered tissue to native tissue (i.e. rigid scaffolds do not match the contractile characteristics of tissues such as capillaries and vascular tubes).
With the ultimate goal of building living tissues and organs capable of successful transplantation into the body and functionality similar to native tissue, bioprinting offers a new and innovative approach. New ideas of emerged from other fields with demonstrated success and potential to answer the problems of current tissue engineering techniques. Utilizing the features of these new advances, the integration of rapid prototyping technology, computer-aided design and tissue engineering brought about bioprinting, also known as organ printing.