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Materials Science in Additive Manufacturing SLA 3D printed triaxial nozzle

aided design (CAD) files. Fused deposition modeling, properties within tissues in the body, thus making them
stereolithography (SLA), digital light processing, and suitable candidates for tissue engineering [11-13] .
selective laser sintering are the several types of 3D printing In tissue engineering and regenerative medicine, 3D
technologies [1,2] . These technologies were first employed extrusion-based bioprinting is frequently utilized to
for product design and development and fast prototyping produce cell-incorporated constructions or scaffolds .
[14]
as they exhibit significantly decrease in lead time and cost; Printability, or the capacity to create and sustain
in recent years, their applications have been broadened repeatable 3D scaffolds from bioink, is crucial in 3D
to high-value production and especially manufacturing. extrusion-based bioprinting (a mixture of biomaterials
Numerous AM technologies have been created, enabling and cells) . Numerous variables or characteristics, such
[15]
the use of a variety of materials for diverse sectors, as those related to the bioink, printing method, and
including improved ceramics, composites, plastics, and scaffold design, have been shown in the research to impact
metals . AM technologies play an increasingly significant printability [14,15] . Soft matter bioinks, such as ultrashort
[3]
role in the biomedical industry, evidenced by the growing self-assembling peptides, are desirable candidates to
trend of AM application in the field of medicine and apply for 3D bioprinting due to their instantaneous
dentistry . gelation properties under physiological conditions, their
[4]
The selection of 3D printing materials is an biocompatibility, and nanofibrous topography resembling
important aspect for consideration because they have an the natural extracellular matrix [16-19] . Our previous research
immediate impact on the characteristics, appearance, explored the development of microfluidic syringe pump
and functionality of the finished product. A wide variety extrusion systems embedded with dual coaxial nozzles to
of materials have evolved with the quick development of accommodate the gelation nature of peptide bioink [20-22] .
3D printing technology, each with distinctive properties The capacity to create and maintain repeatable 3D
and advantages. Polymeric materials are by far the most scaffolds out of bioink using bioprinting technology is
frequently used class of materials for 3D printing due to known as printability. The scaffolds’ structure, which in turn
their ease of processing and low cost . The development impacts their mechanical and biological qualities, depends on
[5]
of 3D-printed polymeric materials is fueling this industry’s their printability. The extrusion-based bioprinting approach
expansion . By using 3D extrusion printing, various can be used to create objects with live cells integrated into
[6]
polymer types, such as thermoplastics, thermosets,
elastomers, and hydrogels, may be treated [5,7] . them. The high water content and cell-friendly environment
of hydrogels make them ideal for this function. Hydrogels
Moreover, an attractive feature of hydrophilic chains can be chemically or physically cross-linked to enable the
that swell in an aqueous environment to generate production of a 3D-bioprinted structure.
hydrogels is their polymeric 3D network. High water Extrusion-based 3D bioprinting and customized
content, shape change, multi-stimuli responsiveness, and 3D printed parts have been explored with respect to the
biocompatibility are some of their numerous material
qualities and capabilities . These materials are especially construction of tissue scaffolds with distinctive characteristics.
[8]
appealing for a wide range of uses, including soft actuators Khan et al. combined vat photopolymerization and extrusion-
based 3D bioprinting to create a complex human-like ear
and sensors, as well as biological and energy applications. structure. Furthermore, Abdelrahman et al. incorporated
[9]
As one of the most extensively studied polymeric materials a hybrid 3D bioprinting and vat photopolymerization
for 3D printing applications, hydrogels are a result of the
fast growth of AM in tissue engineering . approach using dopaminergic neurons to model Parkinson’s
[10]
disease .
[23]
Hydrogels, due to their dynamic character of physical
associations between monomers, are created by non- Hydrogel crosslinking may not happen instantaneously
covalent interactions between their network-forming as the hydrogel may flow or spread, significantly deviating
from the intended design. Moreover, hydrogels are
building blocks that make them suitable for 3D extrusion
printing . Such physical hydrogel systems exhibit shear- challenging to print with, and printed scaffolds can even
[11]
thinning behavior because the weak physical connection fall apart and fail to create a 3D structure. The issue of
is quickly destroyed when pressure is applied. Due to their printability is crucial because the mechanical and biological
extremely mobile and ephemeral non-covalent network, qualities, such as mechanical strength and cell functions, of
[24-26]
hydrogels may also instantly return to their solid state if a printed scaffold might vary from an ideal design .
shear force is removed . As biomaterials, hydrogels have Over-extrusion- or under-extrusion-related flaws,
[12]
been used for decades in 3D cell culture-based research including blobs or holes, are typical quality defects in
applications. They act as scaffolds and can mimic various such systems. A further extrusion failure known as annular

Volume 2 Issue 3 (2023) 2 https://doi.org/10.36922/msam.1786