Micro-poro-elasticity of baghdadite-based bone tissue engineering scaffolds: a unifying approach based on
Hawraa Kariem1, Maria-Ioana Pastrama1, Seyed Iman Roohani-Esfahani2
1Institute for Mechanics of Materials and Structures, Vienna University of Technology (TU Wien), Karlsplatz 13/E202, A-1040 Vienna, Austria.
Abstract:
Microstructure-elasticity relations for bone tissue engineering scaffolds are key to rational biomaterial design. As a contribution thereto, we here report comprehensive length measuring, weighing, and ultrasonic tests at 0.1MHz frequency, on porous baghdadite (Ca3ZrSi2O9) scaffolds. The resulting porosity-stiffness relations further confirm a formerly detected, micromechanically explained, general relationship for a great variety of different polycrystals, which also allows for estimating the zero-porosity case, i.e. Young modulus and Poisson ratio of pure (dense) baghdadite. These estimates were impressively confirmed by a physically and statistically independent nanoindentation campaign comprising some 1750 indents. Consequently, we can present a remarkably complete picture of porous baghdadite elasticity across a wide range of porosities, and, thanks to the micromechanical understanding, reaching out beyond classical elasticity, towards poroelastic properties, quantifying the effect of pore pressure on the material system behavior.
