Table 4.

3D bioprinting strategies

Type	Inkjet-based	Extrusion-based	Light-assisted	Light-assisted	Light-assisted
Subtype	Thermal, piezoelectric, electrostatic	Pneumatic, mechanical (piston-driven, screw-driven)	Scanning-based (LAB, TPP)	Projection-based (DLP)	Projection-based (volumetric)
Fabrication process	Serial: point-by-point	Serial: line-by-line	Serial: point-by-point	Parallel: layer-by-layer	Parallel: rotational
Advantages	Fast printing speed, high resolution, high throughput, low cost	Broad biomaterial selection, scale-up potential, high cell densities, low cost	Very high resolution, compatible with biomaterials in different phases	High resolution, very high speed, good interface integrity, broad biomaterial selection, scale-up potential	Concurrent printing of real 3D structures, scalable to large constructs
Limitations	Poor interface integrity, low cell densities, limited to low viscosity biomaterials	Limited interface integrity, resolution limited by nozzle diameter	High cost, limited biomaterial selection, limited scalability, low throughput	Requires photosensitive biomaterials	Limited resolution, cell density may be limited due to light scattering
Typical resolution	10 μm	100 μm (with cell), 5 μm (acellular)	1 μm	2 μm	mm scale
Bioink viscosity	Low: 3.5 to 12 mPa×s	Wide range: 30 to 6×107 mPa×s	Medium: 1 to 300 mPa×s	-	High viscosity fluids: 90,000 mPa×s, or solids
Cell density	Low :106 cells/ml	High	High: 108 cells/ml	High	-
Print speed	Fast	Medium	Medium	Fast	Fast
Reference	[19,88,104]	[19,88,92]	[19,88,203]	[22,105]	[110]