Modeling of porosity in hydroxyapatite for finite element simulation of nanoindentation test

Abstract This paper presents an approach to design irregular porosities in HA structure with controllable pore shapes and distributions based on the random colloid-aggregation model. Voronoi tessellation was firstly created to convert the HA structure to a collection of partitions. The selected partitions were further merged together to mimic the random colloid aggregations. The fitted B-Spline curves were then used through the vertices of Voronoi cells to outline the boundaries of the irregular-shaped pores. In order to validate the proposed approach, a finite element analysis was conducted on the porous structure models under nanoindentation test. The proposed approach retained the irregular pore shapes, which are generally observed in natural HA structure, while reflecting the significant effect of this irregularity on simulation results. In comparison to other Computer-Aided Design (CAD) techniques, the proposed method could be employed to create more realistic porosities with irregular geometries for accurate simulation of natural HA structure.