Methods of printing a bio-ink on a substrate are provided comprising at least one bio ink layer, said method comprising: i) positioning a printhead comprising a two-dimensional array of print nozzles within proximity of or in contact with a substrate； and ii) ejecting a bio-ink through the print nozzles onto the substrate, forming a bio ink layer, wherein the bio-ink construct comprises at least one bio-ink layer. The methods further encompass methods of printing a live tissue and methods of treating tissue defects.
