3D (Bio) Printing Combined Fiber Fabrication Methods for Tissue Engineering Applications : Possibilities and Limitations

Biofabrication is an emerging interdisciplinary field of engineering that aims to develop technologies for applications in tissue engineering and regenerative medicine. A progressing biofabrication technology is 3D (bio) printing (3DBP), which allows for controlled spatial deposition of cell-laden bioinks in a layer-by-layer approach to fabricate biologically active constructs. Although 3DBP can create some biologically relevant structures, it uses hydrogels, which are isotropic in nature and do not provide sufficient mechanical properties to reconstruct many tissues, such as cartilage, bone, and skin. Additionally, hydrogels alone do not replicate the complex hierarchical buildup of native tissue extracellular matrix (ECM), which contains both gel-like and fibrous components. Replicating native tissue's structure both mechanically and biologically by incorporating fibers would result in enhanced biological performance. This is possible by integrating biofabrication technologies such as 3DBP and fiber fabrication techniques. Thus, harnessing the strengths of each technique and eliminating their limitations. This will enable the fabrication of hybrid 3D constructs with multiscale hierarchy and enhanced mechanical and biological performance comparable to native tissue. This review aims to highlight attempts to combine fiber fabrication methods with 3DBP for tissue engineering applications. Additionally, different fiber fabrication techniques are discussed, showcasing their limitations and possible integration with 3DBP.