TY - JOUR
T1 - Microstructure and micromechanics of the heart urchin test from X-ray tomography
AU - Müter, Dirk
AU - Sørensen, Henning Osholm
AU - Oddershede, J.
AU - Dalby, Kim Nicole
AU - Stipp, Susan Louise Svane
N1 - Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
PY - 2015/9/1
Y1 - 2015/9/1
N2 - The microstructure of many echinoid species has long fascinated scientists because of its high porosity and outstanding mechanical properties. We have used X-ray microtomography to examine the test of Echinocardium cordatum (heart urchin), a burrowing cousin of the more commonly known sea urchins. Three dimensional imaging demonstrates that the bulk of the test is composed of only two distinct, highly porous, fenestrated regions (stereom), in which the thickness of the struts is constant. Different degrees of porosity are achieved by varying the spacing of the struts. Drawing an analogy to vertebrate trabecular bone, where for example, human bone has a connectivity density of ≈1/mm3, we measure up to 150,000 strut connections per mm3. Simulations of mechanical loading using finite element calculations indicate that the test performs at very close to the optimum expected for foams, highlighting the functional link between structure and mechanical properties.
AB - The microstructure of many echinoid species has long fascinated scientists because of its high porosity and outstanding mechanical properties. We have used X-ray microtomography to examine the test of Echinocardium cordatum (heart urchin), a burrowing cousin of the more commonly known sea urchins. Three dimensional imaging demonstrates that the bulk of the test is composed of only two distinct, highly porous, fenestrated regions (stereom), in which the thickness of the struts is constant. Different degrees of porosity are achieved by varying the spacing of the struts. Drawing an analogy to vertebrate trabecular bone, where for example, human bone has a connectivity density of ≈1/mm3, we measure up to 150,000 strut connections per mm3. Simulations of mechanical loading using finite element calculations indicate that the test performs at very close to the optimum expected for foams, highlighting the functional link between structure and mechanical properties.
U2 - 10.1016/j.actbio.2015.05.007
DO - 10.1016/j.actbio.2015.05.007
M3 - Journal article
C2 - 25983316
SN - 1742-7061
VL - 23
SP - 21
EP - 26
JO - Acta Biomaterialia
JF - Acta Biomaterialia
ER -