Abstract Due to limited intrinsic healing capacity of the meniscus, meniscal injuries pose a significant clinical challenge. The most common method for treatment of damaged meniscal tissues, meniscectomy, leads to improper loading within the knee joint, which can increase the risk of osteoarthritis. Thus, there is a clinical need for the development of constructs for meniscal repair that better replicate meniscal tissue organization to improve load distributions and function over time. Advanced three-dimensional bioprinting technologies such as suspension bath bioprinting provide some key advantages, such as the ability to support the fabrication of complex structures using non-viscous bioinks. In this work, the suspension bath printing process is utilized to print anisotropic constructs with a unique bioink that contains embedded hydrogel fibers that align via shear stresses during printing. Constructs with and without fibers are printed and then cultured for up to 56 d in vitro in a custom clamping system. Printed constructs with fibers demonstrate increased cell and collagen alignment, as well as enhanced tensile moduli when compared to constructs printed without fibers. This work advances the use of biofabrication to develop anisotropic constructs that can be utilized for the repair of meniscal tissue.
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Computational Modeling and Experimental Characterization of Extrusion Printing into Suspension Baths
The extrusion printing of inks into suspension baths is an exciting tool, as it allows the printing of diverse and soft hydrogel inks into 3D space without the need for layer‐by‐layer fabrication. However, this printing process is complex and there have been limited studies to experimentally and computationally characterize the process. In this work, hydrogel inks (i.e., gelatin methacrylamide (GelMA)), suspension baths (i.e., agarose, Carbopol), and the printing process are examined via rheological, computational, and experimental analyses. Rheological data on various hydrogel inks and suspension baths is utilized to develop computational printing simulations based on Carreau constitutive viscosity models of the printing of inks within suspension baths. These results are then compared to experimental outcomes using custom print designs where features such as needle translation speed, defined in this work as print speed, are varied and printed filament resolution is quantified. Results are then used to identify print parameters for the printing of a GelMA ink into a unique guest–host hyaluronic acid suspension bath. This work emphasizes the importance of key rheological properties and print parameters for suspension bath printing and provides a computational model and experimental tools that can be used to inform the selection of print settings.
more » « less- NSF-PAR ID:
- 10446365
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- Volume:
- 11
- Issue:
- 7
- ISSN:
- 2192-2640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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