Table 3.

Major parameters that influence the performances of different bioprinting techniques.

Printing Technique	Parameters That Influence Printing Performance	References
Inkjet-based 3D printing	The performance of this printing technique may be influenced by parameters such as printing speed and ink formulation. Indeed, the printing speed can be a challenge for constructing millimeter or centimeter scale biostructures, as maintaining cell viability during many hours of printing is very demanding. Bio-ink formulation influences its volumetric flow rate (i.e., the bio-ink volume that passes through the needle or nozzle per unit of time) and is essential to determine the shape of bioprinted filaments or droplets. In general, higher flow rates are associated with lower printing speeds, leading to an increase in the filament diameter. On the contrary, small flow rates combined with higher printing speeds reduce the filament diameter. Another factor that influences inkjet-based 3D printing is nozzle/extrusion temperature. This is because this parameter dictates the layer thickness of the ink, the printing fidelity and the durability of the cells.	[186,187,188,189]
Extrusion-based 3D printing	Factors such as the applied pressure, nozzle orifice size and geometry play a critical role regarding the printing outcome, since these factors can influence the construct properties such as layer thickness and building orientation. They are also dominant factors that may cause cell damage when printing cell-laden hydrogels. It has been confirmed that cell mortality upon printing is proportional to the nozzle diameter and system pressure employed (increased printing pressure decreases cell viability).	[160,190,191,192,193,194]
Laser-assisted 3D printing	This printing technique is influenced by parameters such as ink formulation, extruder temperature and laser orientation. Ink formulation is particularly relevant since, in addition to influencing the flowrate of the bio-ink, it also influences the rheological properties of bio-inks. These properties dictate printing fidelity, flow behavior, viscosity, shear stress and viscoelasticity of the bio-ink and viability of the cells.	[70,192,193,195,196,197]
Vat polymerization-based printing	The performance of this printing technique will be influenced by parameters such as rheological properties, layer thickness, post-curing time and orientation. Other factors such as exposure time to determine the exposure duration of a single layer, lifting height and speed and lowering speed are crucial parameters that influence the photopolymerization of the associated biopolymer and thus are crucial to determining the printing fidelity.	[198,199,200]