l
Scenario 1: specific regions of the block faces are submitted to
tensile stress in the XX direction (ε xx ) and a shear stress in the
clockwise direction (γ yz ), and the remaining specific regions are
constrained (XX axis rotation).
l
Scenario 2: specific regions of the block faces are submitted to
tensile stress in the YY direction (ε yy ) and a shear stress in the
clockwise direction (γ xz ), and the remaining specific regions are
constrained (YY axis rotation).
l
Scenario 3: specific regions of the block faces are submitted to
tensile stress in the ZZ direction (ε zz ) and a shear stress in the
clockwise direction (γ xy ), and the remaining specific regions are
constrained (ZZ axis rotation).
The obtained results are:
l
Scenario 1: Figure 12a presents a valid topological scaffold
model in two different positions.
l
Scenario 2: Figure 12b presents a valid topological scaffold
model in two different positions.
l
Scenario 3: Figure 12c presents a valid topological scaffold
model in two different positions.
Figure 12 illustrates the topological results for each case study.
Similar to the previous results, these results allow us to conclude
that this type of scaffold design approach enables to produce more
biomimetic topologies. In these particular scenarios, the obtained
geometries now present a higher amount of material internally. In
this case, the scaffolds integrity was lost in the boundaries of the
structures. The goal is not to obtain similar structures as the starting model, but instead to use the starting configuration to produce
novel models with more biomimetic characteristics. It is also possible to observe that the numerical solutions also need to improve
their algorithms when applied to scaffold designs for tissue engineering applications.
4 Discussion
One of the existing computer-based techniques for scaffold design
is topological optimization. The goal of topological optimization is
to find the best use of material for a body that is subjected to either
a single load or a multiple load distribution, maximizing its
mechanical behavior under tensile and shear stress solicitations.
The initial external topology of the μCT data, which corresponds
to a structure of a well-defined mechanical behavior and porosity
level, is the starting point of an optimization scheme that enables to
obtain constructs with different levels of porosity and mechanical
properties, according to the required applications, based on
Biomimetic Boundary-Based Scaffold Design
15
Scenario 1: specific regions of the block faces are submitted to
tensile stress in the XX direction (ε xx ) and a shear stress in the
clockwise direction (γ yz ), and the remaining specific regions are
constrained (XX axis rotation).
l
Scenario 2: specific regions of the block faces are submitted to
tensile stress in the YY direction (ε yy ) and a shear stress in the
clockwise direction (γ xz ), and the remaining specific regions are
constrained (YY axis rotation).
l
Scenario 3: specific regions of the block faces are submitted to
tensile stress in the ZZ direction (ε zz ) and a shear stress in the
clockwise direction (γ xy ), and the remaining specific regions are
constrained (ZZ axis rotation).
The obtained results are:
l
Scenario 1: Figure 12a presents a valid topological scaffold
model in two different positions.
l
Scenario 2: Figure 12b presents a valid topological scaffold
model in two different positions.
l
Scenario 3: Figure 12c presents a valid topological scaffold
model in two different positions.
Figure 12 illustrates the topological results for each case study.
Similar to the previous results, these results allow us to conclude
that this type of scaffold design approach enables to produce more
biomimetic topologies. In these particular scenarios, the obtained
geometries now present a higher amount of material internally. In
this case, the scaffolds integrity was lost in the boundaries of the
structures. The goal is not to obtain similar structures as the starting model, but instead to use the starting configuration to produce
novel models with more biomimetic characteristics. It is also possible to observe that the numerical solutions also need to improve
their algorithms when applied to scaffold designs for tissue engineering applications.
4 Discussion
One of the existing computer-based techniques for scaffold design
is topological optimization. The goal of topological optimization is
to find the best use of material for a body that is subjected to either
a single load or a multiple load distribution, maximizing its
mechanical behavior under tensile and shear stress solicitations.
The initial external topology of the μCT data, which corresponds
to a structure of a well-defined mechanical behavior and porosity
level, is the starting point of an optimization scheme that enables to
obtain constructs with different levels of porosity and mechanical
properties, according to the required applications, based on
Biomimetic Boundary-Based Scaffold Design
15