The correlation of pore morphology, interconnectivity and physical properties of 3D ceramic scaffolds with bone ingrowth.
In the design of tissue engineering scaffolds, design parameters including pore size, shape and interconnectivity, mechanical properties and transport properties should be optimized to maximize successful inducement of bone ingrowth. In this paper we describe a 3D micro-CT and pore partitioning study to derive pore scale parameters including pore radius distribution, accessible radius, throat radius, and connectivity over the pore space of the tissue engineered constructs. These pore scale descriptors are correlated to bone ingrowth into the scaffolds. Quantitative and visual comparisons show a strong correlation between the local accessible pore radius and bone ingrowth; for well connected samples a cutoff accessible pore radius of approximately 100 microM is observed for ingrowth. The elastic properties of different types of scaffolds are simulated and can be described by standard cellular solids theory: (E/E(0))=(rho/rho(s))(n). Hydraulic conductance and diffusive properties are calculated; results are consistent with the concept of a threshold conductance for bone ingrowth. Simple simulations of local flow velocity and local shear stress show no correlation to in vivo bone ingrowth patterns. These results demonstrate a potential for 3D imaging and analysis to define relevant pore scale morphological and physical properties within scaffolds and to provide evidence for correlations between pore scale descriptors, physical properties and bone ingrowth.
Jones
Anthony C
AC
Department of Applied Mathematics, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200, Australia.
Arns
Christoph H
CH
Hutmacher
Dietmar W
DW
Milthorpe
Bruce K
BK
Sheppard
Adrian P
AP
Knackstedt
Mark A
MA
D000465:Algorithms; D001672:Biocompatible Materials / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry*; D004548:Elasticity; D008422:Materials Testing; D008962:Models, Theoretical; D010012:Osteogenesis / Q000502:physiology*; D016062:Porosity; D033081:Shear Strength; D013499:Surface Properties; D023822:Tissue Engineering / Q000295:instrumentation / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry*
D001672:Biocompatible Materials