Characterisation of bone regeneration in 3D printed ductile PCL/PEG/hydroxyapatite scaffolds with high ceramic microparticle concentrations

intramembranous ossification and starts in the central region of pores. Fibrous tissue that resembles non-union tissue within bone fractures is formed within pores that do not have new bone. The amount of blood vessels is similar between scaffolds with mainly fibrous tissue and those with more bone tissue, suggesting vascularization is not a deciding factor for determining the type of tissues regenerated within the pores of 3D printed scaffolds. Multinucleated immune cells are commonly present in all scaffolds surrounding the struts, suggesting a role of managing inflammation in bone regeneration within 3D printed scaffolds.