TY - CHAP A1 - Hilpert, U. A1 - Härtig, F. A1 - Bartscher, M. A1 - Ehrig, Karsten A1 - Staude, Andreas A1 - Goebbels, Jürgen T1 - Messunsicherheit, Kalibrierung und Normale zur zuverlässigen Rückführung der dimensionell messenden Computertomographie (CT) T2 - 4. VDI-Fachtagung Messunsicherheit - Messunsicherheit praxisgerecht bestimmen CY - Erfurt, Deutschland DA - 0208-11-12 PY - 2008 SN - 978-3-98-12624-1-4 IS - Kap. 31 SP - 1 EP - 14 CY - Düsseldorf AN - OPUS4-18600 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Ritter, Z. A1 - Staude, Andreas A1 - Prohaska, S. A1 - Felsenberg, D. ED - Naik, G. R. T1 - Osteocytes characterization using synchrotron radiation CT and finite element analysis N2 - Since a correlation between osteocyte number and their morphology with bone aging or its response to pharmacological treatment appears to exist, a methodology to characterize osteocytes from bone biopsies becomes important. In this chapter, the usage of synchrotron measurements, algorithms for image analysis (Amira, ZIB), and the finite element method using parallelized computational resources for topological analysis of osteocytes is explained and discussed. Different routines normally applied for material characterization of network-like structures (skeletonization) have been adapted to visualize osteocytes along bone cement lines at high resolution (2.174 µm). The different steps concerning to counting osteocytes and analyzing the mechanical behavior of bones are illustrated with an example. Our findings showed a clear alignment of the osteocytes along the cement lines. Interestingly, at the regions near the bone surface with reduced mineralization grade, osteocytes were mainly aligned along the close to high mineralized region. Apparently, not only osteocytes number is reduced with aging but their size increases and they become sparely distributed in comparison with the healthy bone samples from the human mandible. Automatic tetrahedron mesh generation using the "tetragen" tool from Amira worked adequately for meshing the biopsies with a resolution of 20 µm, but meshing biopsies with osteocytes embedded on the bone matrix from the SR-CT samples consumes an enormous amount of time, due to necessary adjustments for avoiding intersections and conserving model closeness. KW - CT KW - Finite element analysis KW - Osteocytes characterization KW - Synchrotron radiation PY - 2012 SN - 978-953-51-0412-4 DO - https://doi.org/10.5772/35242 SP - 165 EP - 190 PB - InTech CY - Rijeka AN - OPUS4-25845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -