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Filament Structure, 3D printing, Bone Repair Scaffolds
into the scaffold as an outer membrane to wrap growth changes such as pH, electric field, magnetic field, and
factors and functional cells with different functions. temperature.
In terms of spatial structure, attempts were made to 5. After continuous optimization and efforts to bring
improve the classical structure by creating microporous bone repair scaffolds into clinical treatment, a
or hydrothermally generating nano-layers on the scaffold marketable clinical application of bone repair
surface; bilayer structure can improve the mechanical scaffolds will be of interest in the future in the field
properties as well as ensure the independence of the slurry of tissue engineering.
while printing multiple materials; core-shell structure 6. The concept of four-dimensional (4D) printing, which
can intelligently adjust the degradation rate of the gives the scaffold structure the property of changing
scaffold materials; and hollow structure provides more over time, opens up a new vision of scaffold function
space for the growth of blood vessels and nerve tissues from a new dimension, and the customized spatial
on the basis of increasing the porosity. There were also arrangement of cells and the activity of cells during the
some specific scaffolds designed on the basis of bionic, printing process, will be the topics of future research.
which can repair human bone defects more precisely
and efficiently after implantation. In terms of biological Acknowledgments
functions, to meet the growing clinical demands, bone This work was supported by China Post-doctoral Science
repair scaffolds are endowed with antibacterial, tumor Foundation (2020M682631), Guangdong Basic and
suppressive, slow drug release, and tissue regenerative Applied Basic Research Foundation (2020A1515011407),
properties in addition to meeting the basic osteogenic National Natural Science Foundation of China
requirements, which help facilitate maximal recovery (52105202, 5210022045), Guangdong academy
while meeting the requirements of bone repair. of science project (2019GDASYL-0103021,
The market scale of bone repair devices sees a 2019GDASYL-0102004/0103018), Guangzhou
continuous expansion while the patients’ requirements Science and Technology Program (201904010280,
for post-operative living standards and the structural 2018A050506056) and Guangdong Basic and Applied
and functional diversity of bone repair scaffolds have Basic Research Foundation (2020A1515011407).
gradually increased. The future development can be
concluded in different aspects: Conflicts of interest
1. In future, the bone repair scaffold is not only similar
to bone tissue in terms of chemical composition No conflict of interest is reported by the author.
(e.g. bioceramics, polymers, cells, and growth References
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56 International Journal of Bioprinting (2021)–Volume 7, Issue 4