title: μCT based assessment of mechanical deformation of designed PTMC scaffolds.
abstract: BACKGROUND
  Advances in rapid-prototyping and 3D printing technologies have enhanced the possibilities in preparing designed architectures for tissue engineering applications. A major advantage in custom designing is the ability to create structures with desired mechanical properties. While the behaviour of a designed scaffold can be simulated using bulk material properties, it is important to verify the behaviour of a printed scaffold at the microstructure level.
  
  
  OBJECTIVE
  In this study we present an effective method in validating the mechanical behaviour of designed scaffolds using a μCT with an in-situ mechanical deformation device.
  
  
  METHODS
  The scaffolds were prepared from biodegradable poly(trimethylene carbonate) (PTMC) by stereolithography and images obtained using a high-resolution μCT with 12.25μm isometric voxels. The data was processed (filtering, segmentation) and analysed (surface generation, registration) to extract relevant deformation features.
  
  
  RESULTS
  The computed local deformation fields, calculated at sub-pore resolutions, displayed expected linear behaviour within the scaffold along the compressions axis. On planes perpendicular to this axis, the deformations varied by 150- 200μm.
  
  
  CONCLUSIONS
  μCT based imaging with in-situ deformation provides a vital tool in validating the design parameters of printed scaffolds. Deformation fields obtained from micro-tomographic image volumes can serve to corroborate the simulated ideal design with the realized product.
authors.affiliation: Department of Electronics and Communications Engineering, Tampere University of Technology, BioMediTech Tampere, Finland.
authors.forename: Nathaniel
authors.initials: N
authors.lastname: Narra
authors.affiliation: Department of Biomaterials Science and Technology, University of Twente, Enschede, The Netherlands.
authors.forename: Sébastien B G
authors.initials: SB
authors.lastname: Blanquer
authors.affiliation: Department of Biomaterials Science and Technology, University of Twente, Enschede, The Netherlands.
authors.forename: Suvi P
authors.initials: SP
authors.lastname: Haimi
authors.affiliation: Department of Biomaterials Science and Technology, University of Twente, Enschede, The Netherlands.
authors.forename: Dirk W
authors.initials: DW
authors.lastname: Grijpma
authors.affiliation: Department of Electronics and Communications Engineering, Tampere University of Technology, BioMediTech Tampere, Finland.
authors.forename: Jari
authors.initials: J
authors.lastname: Hyttinen
mesh_terms: D020341:Absorbable Implants; D004146:Dioxanes / Q000737:chemistry*; D008422:Materials Testing; D010780:Photogrammetry; D011108:Polymers / Q000737:chemistry*; D066330:Printing, Three-Dimensional; D011474:Prosthesis Design; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*; D055114:X-Ray Microtomography
chemical_list: D004146:Dioxanes; D011108:Polymers; C059299:polytrimethylene carbonate
keywords: 3D-printing; MicroCT; PTMC; in-situ deformation; poly(trimethylene carbonate); scaffold design
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