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Liang, et al.
proliferation. Lee et al. reported that human mesenchymal Acknowledgments
stem cell had well-spread morphologies with randomly
multiple lamellipodia on the flat glass plates . They This study was supported by the Shenzhen Science
[60]
further pointed out more cell attachment and spreading and Technology Innovation Commission [Grant No.
occur on the substrates with smaller curvatures. Similar KQTD20190929172505711], Shenzhen Science
and Technology International Cooperation program
conclusions have also been reported [61-63] . As compared [Grant No. GJHZ20200731095606021], Shenzhen
with the P and BCC structure, the CPS scaffolds had more Science and Technology Program [Grant No.
flat plates that might result in tight attachment of more KQTD2017032815444316], and the Guangdong
cells onto the substrates.
Overall, the difference of cell metabolisms shown Province International Collaboration Program [Grant
in these three types of structures could be attributed to No. 2019A050510003]. The authors acknowledge the
different scaffold geometries, which mainly focus on pore assistance of SUSTech Core Research Facilities.
size and surface topology. In detail, higher cell metabolism Conflict of interest
and more cell proliferation of CPS scaffolds could be
observed as compared to that of P and BCC scaffolds, The authors declare that they have no conflicts of
mainly due to the larger pore size and flat surfaces. interest.

4. Conclusions Author contributions
In this work, nano-sized HA ceramic slurry was prepared H.L. performed the preparation and fabrication of the
and processed using DLP 3D printing. Afterward, the scaffolds, and mechanical tests. Y.W. conceived and
P, BCC, and CPS scaffolds with a same porosity were designed the study, and carried out data analysis. S.C.
designed and fabricated under optimized parameters. The and Y.L. performed biological experiments. H.L. and
compressive properties and in vitro biological evaluations, Y.W. wrote and revised the paper with the help from J.B.
such as cell proliferation and attachment morphologies and Z.L.
of three scaffolds, were compared and studied. The main
conclusions are summarized as follows: References
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