AccScience Publishing / IJB / Volume 9 / Issue 6 / DOI: 10.36922/ijb.1233

Strontium-doped calcium silicate scaffolds with enhanced mechanical properties and tunable biodegradability fabricated by vat photopolymerization

Yinjin Li1,2 Jin Su1,2 Annan Chen1,2* Yifei Li1,2 Xi Yuan3 Kezhuo Chen4 Zhaoqing Li5 Chunze Yan1,2 Jian Lu6,7 Yusheng Shi1,2
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1 State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
2 Engineering Research Center of Ceramic Materials for Additive Manufacturing, Ministry of Education, Wuhan 430074, China
3 Department of Orthopedic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
4 Institute of Resource Biology and Biotechnology, Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
5 Wuhan Zeqing Technology Co. Ltd., Wuhan 430074, China
6 Centre for Advanced Structural Materials, Department of Mechanical Engineering, City University of Hong Kong, Hong Kong
7 Centre for Advanced Structural Materials, Department of Mechanical Engineering, City University of Hong Kong, Shenzhen Research Institute, Greater Bay Joint Division, Shenyang National Laboratory for Materials Science, Shenzhen 518057, China
Submitted: 27 April 2023 | Accepted: 21 July 2023 | Published: 14 September 2023
© 2023 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( )

 Strontium-doped calcium silicate (SrCS) bioceramics have demonstrated outstanding vasculogenic ability to repair large segmental bone defects, while their poor mechanical properties and rapid degradation rate remain the major obstacles in clinical treatment. Here, we proposed a novel approach to significantly enhance the mechanical properties of SrCS bioceramics with tunable biodegradability using micron barium titanate-based (BTA) powders as a dopant. Biomimetic SrCS-BTA scaffolds with triply periodic minimal surface structures were fabricated by vat photopolymerization. The effects of BTA content on microtopography, mechanical properties, degradability, and bioactivity of composite scaffolds were studied. On the one hand, the BTA greatly increased the maximum densification rate of SrCS ceramics by 84.37%, while the corresponding densification temperature decreased by 95°C. On the other hand, CaTiO3 generated by the reaction of SrCS and BTA intercepted cracks at the grain boundaries, and thus, the mechanical properties were enhanced due to the pinning effect. The SrCS-40BTA scaffold exhibited much higher compressive strength and elastic modulus by 296% compared with the pure SrCS scaffold. The energy absorption of SrCS-40BTA scaffolds was 5.6 times higher than that of the pure SrCS scaffold. In addition, biocompatible SrCS-BTA scaffolds with lower degradation rates can play a supporting role in the process of repair for a longer duration. This work provides a promising strategy to fabricate biomimetic scaffolds with highly enhanced mechanical properties and tunable biodegradability for repairing damaged large segmental bone tissues.

Strontium-doped calcium silicate
3D print¬ing
Vat photopolymerization
Mechanical property
This work was supported by grants from the National Natural Science Foundation of China (52205363), Fundamental Research Funds for the Central Universities (2019kfyRCPY044 and 2021GCRC002), Program for HUST Academic Frontier Youth Team (2018QYTD04), and Program for Innovative Research Team of the Ministry of Education (IRT1244).
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Conflict of interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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International Journal of Bioprinting, Electronic ISSN: 2424-8002 Print ISSN: 2424-7723, Published by AccScience Publishing