Additively Manufactured Continuous Cell-Size Gradient Porous Scaffolds: Pore Characteristics, Mechanical Properties and Biological Responses In Vitro
Porous scaffolds with graded open porosity combining a morphology similar to that of bone with mechanical and biological properties are becoming an attractive candidate for bone grafts. In this work, scaffolds with a continuous cell-size gradient were studied from the aspects of pore properties, mec...
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MDPI AG
2020-06-01
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| Online Access: | https://www.mdpi.com/1996-1944/13/11/2589 |
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| author | Fei Liu Qichun Ran Miao Zhao Tao Zhang David Z. Zhang Zuqiang Su |
| author_facet | Fei Liu Qichun Ran Miao Zhao Tao Zhang David Z. Zhang Zuqiang Su |
| author_sort | Fei Liu |
| collection | DOAJ |
| description | Porous scaffolds with graded open porosity combining a morphology similar to that of bone with mechanical and biological properties are becoming an attractive candidate for bone grafts. In this work, scaffolds with a continuous cell-size gradient were studied from the aspects of pore properties, mechanical properties and bio-functional properties. Using a mathematical method named triply periodic minimal surfaces (TPMS), uniform and graded scaffolds with Gyroid and Diamond units were manufactured by selective laser melting (SLM) with Ti-6Al-4V, followed by micro-computer tomography (CT) reconstruction, mechanical testing and in vitro evaluation. It was found that gradient scaffolds were preferably replicated by SLM with continuous graded changes in surface area and pore size, but their pore size should be designed to be ≥ 450 μm to ensure good interconnectivity. Both the Gyroid and Diamond structures have superior strength compared to cancellous bones, and their elastic modulus is comparable to the bones. In comparison, Gyroid exhibits better performances than Diamond in terms of the elastic modulus, ultimate strength and ductility. In vitro cell culture experiments show that the gradients provide an ideal growth environment for osteoblast growth in which cells survive well and distribute uniformly due to biocompatibility of the Ti-6Al-4V material, interconnectivity and suitable pore size. |
| first_indexed | 2024-03-10T19:19:53Z |
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| id | doaj.art-68ffa5ee3a4041378da187778226f3ae |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-10T19:19:53Z |
| publishDate | 2020-06-01 |
| publisher | MDPI AG |
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| spelling | doaj.art-68ffa5ee3a4041378da187778226f3ae2023-11-20T03:01:58ZengMDPI AGMaterials1996-19442020-06-011311258910.3390/ma13112589Additively Manufactured Continuous Cell-Size Gradient Porous Scaffolds: Pore Characteristics, Mechanical Properties and Biological Responses In VitroFei Liu0Qichun Ran1Miao Zhao2Tao Zhang3David Z. Zhang4Zuqiang Su5School of Advanced Manufacturing Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, ChinaCollege of Communication and Information Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, ChinaState Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, ChinaState Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044, ChinaCollege of Engineering, Mathematics and Physical Sciences, University of Exeter, North Park Road, Exeter EX4 4QF, UKSchool of Advanced Manufacturing Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, ChinaPorous scaffolds with graded open porosity combining a morphology similar to that of bone with mechanical and biological properties are becoming an attractive candidate for bone grafts. In this work, scaffolds with a continuous cell-size gradient were studied from the aspects of pore properties, mechanical properties and bio-functional properties. Using a mathematical method named triply periodic minimal surfaces (TPMS), uniform and graded scaffolds with Gyroid and Diamond units were manufactured by selective laser melting (SLM) with Ti-6Al-4V, followed by micro-computer tomography (CT) reconstruction, mechanical testing and in vitro evaluation. It was found that gradient scaffolds were preferably replicated by SLM with continuous graded changes in surface area and pore size, but their pore size should be designed to be ≥ 450 μm to ensure good interconnectivity. Both the Gyroid and Diamond structures have superior strength compared to cancellous bones, and their elastic modulus is comparable to the bones. In comparison, Gyroid exhibits better performances than Diamond in terms of the elastic modulus, ultimate strength and ductility. In vitro cell culture experiments show that the gradients provide an ideal growth environment for osteoblast growth in which cells survive well and distribute uniformly due to biocompatibility of the Ti-6Al-4V material, interconnectivity and suitable pore size.https://www.mdpi.com/1996-1944/13/11/2589additive manufacturingselective laser meltinggraded porous scaffoldtriply periodic minimal surfacesmechanical behaviorpore characteristics |
| spellingShingle | Fei Liu Qichun Ran Miao Zhao Tao Zhang David Z. Zhang Zuqiang Su Additively Manufactured Continuous Cell-Size Gradient Porous Scaffolds: Pore Characteristics, Mechanical Properties and Biological Responses In Vitro Materials additive manufacturing selective laser melting graded porous scaffold triply periodic minimal surfaces mechanical behavior pore characteristics |
| title | Additively Manufactured Continuous Cell-Size Gradient Porous Scaffolds: Pore Characteristics, Mechanical Properties and Biological Responses In Vitro |
| title_full | Additively Manufactured Continuous Cell-Size Gradient Porous Scaffolds: Pore Characteristics, Mechanical Properties and Biological Responses In Vitro |
| title_fullStr | Additively Manufactured Continuous Cell-Size Gradient Porous Scaffolds: Pore Characteristics, Mechanical Properties and Biological Responses In Vitro |
| title_full_unstemmed | Additively Manufactured Continuous Cell-Size Gradient Porous Scaffolds: Pore Characteristics, Mechanical Properties and Biological Responses In Vitro |
| title_short | Additively Manufactured Continuous Cell-Size Gradient Porous Scaffolds: Pore Characteristics, Mechanical Properties and Biological Responses In Vitro |
| title_sort | additively manufactured continuous cell size gradient porous scaffolds pore characteristics mechanical properties and biological responses in vitro |
| topic | additive manufacturing selective laser melting graded porous scaffold triply periodic minimal surfaces mechanical behavior pore characteristics |
| url | https://www.mdpi.com/1996-1944/13/11/2589 |
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