Abstract
Driving the field of micro computed tomography toward more quantitative, rather than qualitative, approaches, we here present a new evaluation method, which uses the unique linear relationship between gray values and x-ray attenuation coefficients, together with the energy-dependence of the latter, to identify (i) the average x-ray energy used in the CT device, (ii) the x-ray attenuation coefficients, and (iii), via the x-ray attenuation average rule, the intravoxel composition, i.e., the microporosity, which, amongst others, governs the voxel-specific mechanical properties, such as stiffness and strength. The method is realized for six 3D tricalcium phosphate scaffolds, seeded with pre-osteoblastic cells and differentiated for 3, 6, and 8 weeks, respectively. The corresponding voxel-specific microporosities turn out to increase during the culturing period (resulting in reduced elastic properties, as determined from micromechanical considerations), while the overall macroporosity remains constant. The new methods are expected to further foster the development of a rationally based and computer-aided design of biomaterials and tissue engineering scaffolds.
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ACKNOWLEDGMENTS
The authors are grateful for the financial support through the ERASMUS network, and through COST Action MP1005 NAMABIO, making the cooperation between the Reykjavik University and the Vienna University of Technology (TU Wien) possible. Moreover, the Viennese researchers gratefully acknowledge the support from the European Research Council (ERC), in the course of project #257023, MICROBONE.
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Czenek, A., Blanchard, R., Dejaco, A. et al. Quantitative intravoxel analysis of microCT-scanned resorbing ceramic biomaterials–Perspectives for computer-aided biomaterial design. Journal of Materials Research 29, 2757–2772 (2014). https://doi.org/10.1557/jmr.2014.326
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DOI: https://doi.org/10.1557/jmr.2014.326