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International Journal of Bioprinting Comparison of different 3D printing technologies

Today’s 3D printing methods can produce parts The aim of this work is, first, to study the printability of
in a single operation, producing them fully assembled different materials with potential for use in 3D bioprinting.
or, alternatively, facilitating the assembly process . In To this end, tools will be designed using 3D printing to allow
[2]
addition, objects are modeled and printed with a high the complete characterization of different biocompatible
degree of structural and spatial control, creating and materials using a 3D bioprinter. This will make it possible
optimizing objects that cannot be built with traditional to quantify and standardize the results obtained by being
processes. able to control different variables, such as environmental
humidity, printing temperature, or amount of material
This technology has wide applications in different
fields : automotive (producing spare parts, creating printed. The second objective is to compare the results
[3]
obtained and study the uses of hydrogel and thermoplastic
production mechanisms); aerospace (creating complex structures obtained using additive manufacturing
parts); healthcare (operations planning, implant and technologies (3D printing and 3D bioprinting).
prosthetic development, tissue bioprinting, medical
training); retail (customized toys, use in simple repairs); etc. These two lines of study are becoming increasingly
important in the field of medicine. In order to carry them
3D printing is expanding its use in the field of health out, the combination of 3D bioprinting with specialized
thanks to the manufacture of medical prostheses due computer-aided design (CAD) software will be considered,
to the high adaptability of each part created to the exact making it possible to manufacture biomimetic 3D
characteristics of the patient . The integration of 3D structures.
[4]
printing and biomimicry promotes improvements in
the manufacture of functional materials and structures, 2. Materials and methods
which will lead to advances in various applications in the
biomedical industry [5,6] . Tissue engineering also offers 2.1. Starting materials
very interesting solutions for regenerative medicine by The following source materials were used in this study:
combining cells, growth factors, biomaterials, and 3D
printing technology to produce biological constructs in the 2.1.1. ColMA Lyophilizate
desired shape, thus giving rise to 3D bioprinting. Methacrylated type 1 collagen (ColMA), supplied by
CELLINK, is a hybrid hydrogel, which is obtained by the
3D bioprinting is a process of manufacturing functional addition of photoactive methacrylate groups, allowing
tissues and organs from biomaterials by means of computer it to be cross-linked by the activation of a photoinitiator
software that generates a 3D model. The process involves to provide the hydrogel with improved structural
the addition of successive layers of biomaterial, with the properties .
[11]
added difficulty that, being living material, it must be
carried out under conditions that ensure the survival and 2.1.2. LAP photoinitiator
proliferation of the cells [7-9] . The lithium salt LAP (lithium phenyl-2,4,6-
trimethylbenzoylphosphinate) is a free radical photoinitiator
To do this, first, the tissue or organ is digitized using used to initiate the chain polymerization reaction after
some image processing technology (magnetic resonance, exposure to light and is combined with the different
ultrasound...) in order to generate a 3D model. Subsequently, methacrylated bioinks, such as ColMA or gelatin
this digital model is converted into a Standard Triangle methacryloyl (GelMA), to produce a photopolymer used
Language (STL) format file or, failing that, the type of in bioprinting . The LAP photoinitiator was supplied by
[12]
file read by the bioprinter we are going to use. Finally, CELLINK.
the biological part consists of obtaining and cultivating
the cells. This step is key, as it requires choosing the right 2.1.3. Reconstitution Agents A and P
bioinks to emulate the tissue to be manufactured. Once the Reconstitution Agent A is an acetic acid solution for
tissue or organ has been printed, it is kept in the bioprinter dissolving and diluting freeze-dried CELLINK bioinks
for maturation before it can be used or studied . that include collagen in their composition, such as Coll1
[10]
The application of these additive printing technologies Lyophilizate and ColMA Lyophilizate. The reconstituted
has, for example, exploded in popularity in the dental collagen solutions, in combination with the collagen buffer,
sector, which has started to use them in recent years. The make the bioink isotonic and the pH easier to neutralize.
World Dental Federation (FDI) states that oral health is Reconstitution Agent P is ideal for dissolving
paramount to the maintenance of general health and well- and diluting GelMA Lyophilizate and hyaluronic
being. A healthy and functional dentition is a key indicator acid methacrylate (HAMA) Lyophilizate for bioink
of quality of life. formulation. Having physiological pH and isotonicity due

Volume 9 Issue 3 (2023) 27 https://doi.org/10.18063/ijb.680