Advances in Hybrid Fabrication toward Hierarchical Tissue Constructs

Abstract

The diversity of manufacturing processes used to fabricate 3D implants, scaffolds, and tissue constructs is continuously increasing. This growing number of different applicable fabrication technologies include electrospinning, melt electrowriting, volumetric‐, extrusion‐, and laser‐based bioprinting, the Kenzan method, and magnetic and acoustic levitational bioassembly, to name a few. Each of these fabrication technologies feature specific advantages and limitations, so that a combination of different approaches opens new and otherwise unreachable opportunities for the fabrication of hierarchical cell–material constructs. Ongoing challenges such as vascularization, limited volume, and repeatability of tissue constructs at the resolution required to mimic natural tissue is most likely greater than what one manufacturing technology can overcome. Therefore, the combination of at least two different manufacturing technologies is seen as a clear and necessary emerging trend, especially within biofabrication. This hybrid approach allows more complex mechanics and discrete biomimetic structures to address mechanotransduction and chemotactic/haptotactic cues. Pioneering milestone papers in hybrid fabrication for biomedical purposes are presented and recent trends toward future manufacturing platforms are analyzed.

An open-source handheld extruder loaded with pore-forming bioink for in situ wound dressing

“…The three-dimensional (3D) bioprinting technologies have been rapidly advancing over the past decade as an outcome of the increasing demand for functional human tissues and organs, used toward either regenerative medicine or drug development [ 1 ]. Indeed, immense potential of this class of enabling technologies has been demonstrated over the years [ [2] , [3] , [4] , [5] , [6] ]. Nevertheless, the tissue defects usually feature curved surfaces or even more intricate geometries in a wound-specific manner.…”

Polymers for Melt Electrowriting

“…One general approach to improve deficiencies in scaffold fabrication is to combine different manufacturing processes overcoming limitations in any single technology. Hybrid fabrication [105] and a detailed summary of hybrid developments using MEW are given by Afghah et al [106] Using composite materials and techniques offers promising strategies to combine advantageous properties of different materials or techniques to one design approach ( Figure 6).…”

Turning Nature’s own processes into design strategies for living bone implant biomanufacturing: a decade of Developmental Engineering

“…This is a growing field of interest, requiring the merger of multiple biofabrication technologies resulting in hybrid strategies. For a review of this trend, see Dalton et al (2020) [ 161 ].…”