Although 3D printing has theability to fabricate on-demand, highly personalized complex designs at lowcosts, this technology’s medical applications are limited due to lack ofdiversity in biomaterials. Even with the availability of variety ofbiomaterials including metals, ceramics, polymers and composites, medical 3Dprinting is still confined by factors such as biomaterial printability, controlof their biodegradation and biocompatible properties. Usually, inextrusion based bioprinting, higher concentrations of polymers are used infabricating bioinks to obtain structural integrity of the end product. Thisdense hydrogel environment limits cellular network and functional integrationof the scaffold. For any moderate sized biological scaffold to be functional,vascularization is utmost important and is not possible with the current 3Dprinting technology.
Small scale scaffolds currently printed in thelaboratories of researchers can easily survive through diffusion, but alive-size functional organ must have a profuse vascularization. To address thisproblem, sacrificial materials during the scaffold fabrication have been usedby many researchers. These materials fill up the void spaces providing mechanicalsupport to the printing materials and once constructs are fabricated they areremoved by post-processing methods. Many sacrificial/fugitive materialsincluding carbohydrate glass 44, pluronic glass 45, gelatin microparticles 46 have been used for thispurpose 47.