AccScience Publishing / IJB / Volume 10 / Issue 1 / DOI: 10.36922/ijb.1067

Additive-manufactured synthetic bone model with biomimicking tunable mechanical properties for evaluation of medical implants

Ju Chan Yuk1 Kyoung Hyup Nam2* Suk Hee Park1*
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1 School of Mechanical Engineering, Pusan National University, Busan 46241, Republic of Korea
2 Department of Neurosurgery, Medical Research Institute, Pusan National University Hospital, Pusan National University School of Medicine, Busan 46241, Republic of Korea
IJB 2024, 10(1), 1067
Submitted: 12 June 2023 | Accepted: 3 August 2023 | Published: 10 January 2024
© 2024 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 ( )

Additive manufacturing has enabled the customization of biomedical systems, including transplantable medical devices, to achieve mechanical biocompatibility. For bone implants, patient-specific bone models must be used to evaluate the mechanical properties of implant compression and subsidence. This study proposes a methodology for designing and fabricating bone models to evaluate patient-specific bone implants. The method involves three-dimensional printing of infill-varied structure, with alternating high-low-high infill density regions, which undergo sequential deformation from the surficial region during compression with an implant. Based on this deformation behavior, the relationship between infill density parameters and mechanical properties was confirmed with the tunability of mechanical properties involving stiffness and failure load. The infill-varied design was applied to the inner structures of artificial vertebra models based on computed tomography scans for cadaver specimens. By tailoring the infill density conditions, the stiffness and failure load were approximated to those of the natural vertebrae. Furthermore, this infill-varied artificial vertebra could be used to evaluate additive-manufactured patient-specific implants. The patient-specific implant had greater resistance to subsidence than the commercial implant, suggesting the feasibility of a biomimicking bone model. The bone-mimetic infill-varied structure could be used to evaluate patient-specific manufactured implants and could be applied to other bone engineering structures with optimized biomechanical properties.

Additive manufacturing
3D printing
Tunable mechanical properties
Bone model
Implant evaluation
This work was supported by grants of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (HI21C1350), and the Korea Basic Science Institute (National Research Facilities Equipment Center) grant funded by the Ministry of Education (Grant no. 2021R1A6C101A449).
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Conflict of interest
The authors declare no conflicts of interest.
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