Table 2.

Summary of the potential of ultrasound in 3D bioprinting.

Imaging	Sonography has much lower resolution than MRI and CT to illustrate the composition and structure of tissue clearly. But it can monitor the condition of bioprinted parts in vivo in real time at much lower cost.
Bioink preparation	USWF can generate various types of cell spheroids efficiently and quickly in a high cell viability using easy operation. Design of the device and optimization of operating parameters need specific knowledge, acoustics.
Tissue fusion	Acoustic field may be beneficial in enhancing the tissue fusion by the acoustic radiation force or mechanical vibration, which needs more experimental evidence.
Tissue maturation	LIUS could enhance the differentiation of stem cells effectively and highly compatible with the current bioreactors and tissue maturation approaches. Appropriate control of the release of growth factor at different stages of tissue maturation using different cell types is challenging.