Biomechanical performances of PCL/HA micro- and macro-porous lattice scaffolds fabricated via laser powder bed fusion for bone tissue engineering

The present experimental study aims to extend know-how on resorbable polycaprolactone/hydroxyapatite (PCL/HA, 70/30 wt%) scaffolds, produced by Laser Powder Bed Fusion (LPBF) technology, to geometrically complexlattice structures and micro porous struts. Using optimized LPBF printing parameters, micro- and macro-porousscaffolds for bone tissue regeneration were produced by regularly repeating in space Diamond (DO) and RhombicDodecahedron (RD) elementary unit cells. After production, scaffolds were submitted to structural, mechanical,and biological characterization. The interaction of scaffolds with human Mesenchymal Stem Cells (hMSCs)allowed studying the degradative processes of the PCL matrix. Biomechanical performances and biodegradationof scaffolds were compared to literature results and bone tissue data. Mechanical compression test, biologicalviability up to 4 days of incubation and degradation rate evidenced strong dependence of scaffold behavior onunit cell geometry as well as on global geometrical features.