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Revealing emerging science and technology research for dentistry applications of 3D bioprinting
Competitive Technology Intelligence involves the 3D medical imaging such as computed tomography, 3D
analysis of S&T environment. Moreover, it has been printing permits the fabrication of personalized constructs
applied for years in different industries; however, in the (patient-specific) .
[15]
field of 3D printing and, moreover, for bio-applications, 3D bioprinting was first introduced by Thomas Boland
the studies are still scarce. In this sense, Rodríguez- in 2003; he patented the use of inkjet 3D printing for
Salvador et al. (2017) combined competitive technology cells . According to a recent publication by the founder
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[1]
intelligence with scientometrics tools to analyze scientific of one of the biggest 3D bioprinting centers, Antony Atala,
and patent literature from 2000 to mid-2016, determining 3D bioprinting is based on three central approaches:
the knowledge landscape on 3D bioprinting. On the Biomimicry, autonomous-self-assembly, and mini-tissue
other hand, Trappey et al. evaluated the development building blocks . Biomimicry consists of the creation
[2]
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of 3D printing technology for biomedical applications of exact replicas of the cellular and extracellular parts of
through a US patent analysis where a search time frame a tissue and organ . Self-assembly is the scaffold-free
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was set from 1980 to August 2014. While both studies method that mimics the behavior of embryonic stem
analyze 3D printing from a general perspective, this cells. Finally, mini-tissues can be defined as the smallest
research pursues to fill the gap associated to the lack of structural and functional component of a tissue . In the
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competitive technology studies on specific applications review of the field by Murphy and Atala, they suggest that
of 3D bioprinting, in this case by analyzing its innovative the combination of these three mentioned approaches are
presence on dentistry. needed in order to print complex 3D biological structures
with multiple functionality, structure, and mechanical
1.2 3D Bioprinting properties .
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3D printing is a revolutionary technology that is also The main technologies used for 3D bioprinting
known as additive manufacturing. The American Society living and biological materials are inkjet, laser-assisted
for Testing and Materials (ASTM International) define printing, and micro-extrusion. Different specifications
additive manufacturing as a group of techniques which and features of them have to be contemplated based on
apply the additive shaping principle and thereby build the most important factors that affect bioprinting which
physical 3D geometries by successive addition of material. are a resolution, cell viability, and the materials used for
Hence, it is important to clarify that according to the printing. Inkjet 3D printing is a non-contact (nozzle away
ASTM the terminology of 3D printing can also be used as from the substrate) printing technology where 2D and
synonymous of additive manufacturing in a non-technical 3D structures are generated using picoliter ink droplets
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context (Cerneels, 2015; ISO/ASTM 52900, 2015). The jetted onto a substrate following a digital pattern . The
application of this technology is growing because it usual amount of material dispensed is between 1 and
offers unique characteristics, such as customization, the 100 picoliters allowing very high resolution. All drops
production of complex geometries and waste reduction. are spherical in flight and identical to their neighbors .
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The principal processes of 3D printing involve the Several mechanisms can be used to generate the bioink
following: Fused deposition modeling , selective laser droplets, the most frequently used for cells are thermal
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sintering , electron beam melting , inkjet 3D printing , and piezoelectric. In the thermal method, a heat generator
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extrusion 3D printing , and laser-assisted printing . As increases the temperature up to 300°C within the
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a diverse number of industries, ranging from automotive chamber. Then, the heating produces a bubble which
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and aerospace to health, have a growing interest in the expels the droplet . With the piezo-electric method, a
development and implementation of this technology; direct mechanical pulse is applied to the bioink which
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knowing scientific and technology trends will play a results in the ejection of the droplet .
fundamental role to identify and manage opportunities to A standard laser assisted bioprinting (LAB) set-up
innovate. is usually composed of three elements: A pulsed laser
In recent years, the use of these technologies for source, a target coated with the material to be printed
medical applications has increased , and as a result, the (the ribbon) and a receiving substrate. Depending on the
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term 3D bioprinting has born as a specialized class of bioink optical absorption and the laser wavelength, a laser
3D printing. 3D bioprinting is a layer by layer precise absorbing interlayer may be necessary to induce transfer
positioning of biological materials and living cells . and is placed between the support and the bioink . LAB
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Some applications of 3D bioprinting include stem cell functions using focused laser pulses on the absorbing
research , cancer model , drug testing , and tissue layer of the ribbon to generate a high-pressure bubble
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engineering . In tissue engineering, for manufacturing that propels cell-containing materials toward the collector
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scaffolds, these technologies are able to control pore substrate. This technology allows for the precise deposition
size, shape, distribution, and interconnectivity of pores. of materials and high densities of cells in relatively small
In addition to this, combined with the ability CAD and 3D structures without affecting cell viability .
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2 International Journal of Bioprinting (2019)–Volume 5, Issue 1