Chapter 17: Clinical Application and Regulation of Bioprinting Biomaterials Focusing on Hydrogels

Bioprinting technology is emerging as a major innovation for replacing or repairing the tissues in the file category of tissue engineering, and this is specifically related to regenerative medicine. In this process, hydrogels-containing living cells are precisely placed in a predefined position, to form three-dimensional (3D) constructions of physically and biologically tissue-mimetic complex structures. In this sense, hydrogels are hydrophilic, three-dimensional networks that can absorb large quantities of water or biological fluids and thus have the potential to be used as prime candidates for carriers or matrices for cells in tissue engineering. Importantly, hydrogels are used in 3D bioprinting and are important components that affect the printing process. The hydrogels allow printed constructs to be assembled into 3D form and the hydrogels encapsulating cells, called bioink, to protect the cells in 3D conditions from any mechanical damage that might occur during the printing process. The bioink forms a matrix environment and supports cell growth in the printed constructs. This review describes the currently used hydrogels for 3D bioprinting and the potential clinical application of this process for tissue regeneration.