Page 248 - IJB-9-2

International Journal of Bioprinting Coronary and peripheral artery disease. State of the art.

Figure 11. (A) Schematic representation of stent parts and nomenclature. (B) Geometrical design of commercial NIRxcell stent, which possesses different
strut widths within the same structure. (C) Some examples of strut connections. (D) Non-uniform Poisson’s ratio stent 2D structure. Reproduced with
permission from [82] 2021, Micromachines.

[82]
mechanical properties, as recently reviewed by Pan et al. of view, 3DP is also useful in the production of stents with
Within these stents, it is possible to differentiate between different geometries enabling the study of the influence
[28]
“closed cells” and “open cells” (Table 3) . Nowadays, it is that each design would be upgraded to as a medical
also possible to find commercial stents with different strut device. Therefore, 3DP is the perfect method for rapidly
TM
width in the same device, such as NIRxcell stent system confirming or denying computational studies.
(Figure 11B) and others with non-uniform cell sizes and Misra et al. used computational studies to explore
shapes (Figure 11D).
different PCL-GR geometries and simulate the deformation
The preparation of different stent designs and the of the stent during crimping and expansion . The
[70]
experimental study of their correlation with stent simulations helped to discern the most optimal stent
performance and future complications is not feasible design, thus accelerating the production of the CAD model
from an experimental point of view due to the milieu for 3DP. In a similar way, Cabrera et al. used computational
of possible designs (Table 3), dimensions, materials, studies to translate the results into a physical polymer
hemodynamics, etc., together with the long-term studies prototype through FDM 3DP . The idea was to fabricate
[85]
and the number of replicates. For example, some authors a stent with a flexible, BRS thermoplastic co-polyester
and manufacturers advocate for stents with thinner elastomer (TPC) having physical properties similar to
struts to improve and aid re-endothelialization [83,84] , but that of a commercially available nitinol stent, including
this can significantly influence the VS deliverability, self-expanding ability. Computational studies enabled the
flexibility, friction, amount of vessel wall coverage, and anticipation and adjustment of the final stent performance
drug delivery, if applicable. In this regard, computational by changing the width, thickness, and strut number. After
studies or in silico studies are of great usefulness, enabling selecting the desirable stent parameters, dimensions and
digital simulations to predict the final properties and geometry as well as obtaining adequate crimping and
performance of a particular stent. From a medical point crush computational results, the TPC stent was printed
of view, 3DP is an especially robust, versatile technique with FDM. The experimental mechanical studies were in
for the manufacturing of personalized, in situ VS prior agreement with the computational models, confirming
to the surgical intervention and adapted to the particular the ability of computational simulations to build realistic
type of lesion and blood vessel. From the research point prototypes.

Volume 9 Issue 2 (2023) 240 https://doi.org/10.18063/ijb.v9i2.664