Introduction
3D printing techniques have made in-house manufacturing widely available for small companies, laboratories, and even common households. Larger organizations have also been able to use 3D printing by providing services more quickly to more people with more types of needs. Its applications are seemingly countless while ease of use is quickly learned and publicly available. Individuals can design and create custom hardware with varying types of materials. 3D printing is being implemented in everything from construction to education to art and now medicine¹.
The additive process of 3D printing constructs objects layer by layer from the bottom up. Designs are mostly drafted from computer-automated design programs such as AutoCAD and SolidWorks. Some CAD software is even open-source, accessible by any with an interest without a price tag. The digital models are then sliced into layers (usually in a separate program) to be comprehensible by the printer. Similar to inkjet techniques, each layer is printed line by line in order. The duration of the process varies widely, from minutes to days, depending on the size of the model and the type of material being used². Materials can be chosen for their rigidity, flexibility, conductive properties, and biocompatibility³. More complex projects can utilize multiple types of materials if the printer is capable as some materials require selective lasering or other hardening methods².
Use cases
In the medical field, biomaterials, tissues, and cells are being used in 3D bioprinting. The overall process is nearly identical to non-biological applications. 3D models can be custom made or acquired by imaging techniques like CT and MRI scanning and segmented to the area of interest before slicing into layers. The printer and material are uniquely selected for the biological process. Biomimetics, autonomous self-assembly, and mini-tissue-building blocks⁴ are three basic principles of 3D bioprinting. Biomimetics is the mimicking of biological processes and is used here to solve human problems with biocompatible solutions. Autonomous self-assembly simulates embryonic organ development by modularly guiding cells and tissue into becoming the target organ. Mini-tissue-building blocks are the smallest functional structures and components of tissues that can be assembled to form a complete construct⁵.
The potential of 3D bioprinting for the advancement of healthcare is vast and inspiring. Already, it is being used to print grafts for skin and bone transplant⁶. Scaffolding techniques allow for less uniform structures like ears and facial reconstruction. Perhaps most importantly are the advancements in organ printing enabling patients to completely bypass donor waiting lists with custom tailored organs made from their very own cells⁷. There are, of course, many years of testing, studies, and wading through necessary regulatory review and approval before we can truly benefit from this technology; however, the work is promising, and the outlook is optimistic.
Written by: Mathew Loren
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References
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Wu, Chin-San (2021). Polymer 3D Printing Review: Materials, Process, and Design Strategies for Medical Applications. Polymers (Basel), 13(9): 1499. DOI: 10.3390/polym13091499
Papaionnou, T., Manolesou, D., Dimakakos, E., Tsoucalas, G., Vavuranakis, M., Tousoulis, D. (2019). 3D Bioprinting Methods and TechniquesL Applications on Artificial Blood Vessel Fabrication. Acta Cardiol Sin, 35(3): 284-289. DOI: 10.6515/ACS.201905_35(3).20181115A
Pharma, E. (2017, June 1). Revolutionizing Business Through 3D Printing Emery Pharma. https://emerypharma.com/blog/revolutionizing-business-through-3d-printing/
Baltazar, T., Merola, J., Catarino, C., Xie, C. B., Kirkiles-Smith, N. C., Lee, V., Hotta, S., Dai, G., Xu, X., Ferreira, F. C., Saltzman, W. M., Pober, J. S., & Karande, P. (2020). Three Dimensional Bioprinting of a Vascularized and Perfusable Skin Graft Using Human Keratinocytes, Fibroblasts, Pericytes, and Endothelial Cells. Tissue Engineering Part A, 26(5–6), 227–238. https://doi.org/10.1089/ten.tea.2019.0201
Wong, X. (2019). Advanced Polymers for Three-Dimensional (3D) Organ Bioprinting. Micromachines (Basel), 10(12):814. DOI: 10.3390/mi10120814
Kunwar, D. (2019, December 28). The Uncertainty of Regulating 3D Organ Printing. The Regulatory Review. https://www.theregreview.org/2019/12/10/kunwar-uncertainty-regulating-3d-organ-printing/