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Noroozi, et al.:
each other, so the resulting force on the knee joint will LOTUS-NDT scanner, and image processing and analysis
be an eccentric force. The stress fields in the scaffold will services. They also gratefully acknowledge the partial
help the designer to optimize the structural integrity of support from European Union’s Horizon 2020 research
the component (Figure 17). and innovation program (H2020-WIDESPREAD-2018,
In addition, the interaction between the designed SIRAMM) under grant agreement No. 857124.
scaffold and live tissues and molecules, which are the
foundations of the growth mechanism, can be calculated Conflict of interest
from the FEM results of µCT scans. Thus, the FEM-µCT The authors declare that they have no known competing
simulation is a powerful tool in the hands of the tissue financial interests or personal relationships that could
engineer to study the effect of different factors. have appeared to influence the work reported in this paper.

4. Conclusions Author contributions
Different scaffolds with different transition zones were Conceptualization, R.N., A.H., and M.B. Data curation,
designed and 3D printed by employing the FDM process. R.N. and F.T. Formal analysis, R.N., F.T., A.Z., R.B.,
First, single-cell type structures, including diamond, I-WP, M.A.S., A.R.G., A.H., and M.B. Investigation, R.N.
and gyroid, were designed and printed. It has been shown Methodology, R.N., A.H., and M.B. Supervision, A.H.
that the diamond structure was stiffer than others as the and M.B. Visualization, R.N. and F.T. Writing – original
porosity plays a significant role on the scaffold’s behavior. draft, R.N. and F.T. Writing – review and editing, R.N.,
The results showed that the effect of the transitional F.T., A.Z., R.B., M.A.S., A.R.G., A.H., and M.B. All
zone is less important than that of the porosity; in other authors have read and agreed to the published version of
words, the results of compression test revealed that some the manuscript.
scaffolds with sudden transitional zones but lower porosity
in comparison with other scaffolds had higher Young’s References
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The authors would like to acknowledge Behin Negareh 9. Yang Y, Wang G, Liang H, et al., 2019, Additive Manufacturing
Co., Ltd., Tehran, Iran, for µCT imaging using their of Bone scaffolds. Int J Bioprint, 5:148.

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