Development of a synthetic tissue engineered three-dimensional printed bioceramic-based bone graft with homogenously distributed osteoblasts and mineralizing bone matrixin vitro

Abstract

Over the last decade there have been increasing efforts to develop three-dimensional (3D) scaffolds for bone tissue engineering from bioactive ceramics with 3D printing emerging as a promising technology. The overall objective of the present study was to generate a tissue engineered synthetic bone graft with homogenously distributed osteoblasts and mineralizing bone matrix in vitro, thereby mimicking the advantageous properties of autogenous bone grafts and facilitating usage for reconstructing segmental discontinuity defects in vivo. To this end, 3D scaffolds were developed from a silica-containing calcium alkali orthophosphate, using, first, a replica technique -the Schwartzwalder-Somers method -and, second, 3D printing, (i.e. rapid prototyping). The mechanical and physical scaffold properties and their potential to facilitate homogenous colonization by osteogenic cells and extracellular bone matrix formation throughout the porous scaffold architecture were examined. Osteoblastic cells were dynamically cultured for 7 days on both scaffold types with two different concentrations of 1.5 and 3 × 10 9 cells/l. The amount of cells and bone matrix formed and osteogenic marker expression were evaluated using hard tissue histology, immunohistochemical and histomorphometric analysis. 3D-printed scaffolds (RPS) exhibited more micropores, greater compressive strength and silica release. RPS seeded with 3 × 10 9 cells/l displayed greatest cell and extracellular matrix formation, mineralization and osteocalcin expression. In conclusion, RPS displayed superior mechanical and biological properties and facilitated generating a tissue engineered synthetic bone graft in vitro, which mimics the advantageous properties of autogenous bone grafts, by containing homogenously distributed terminally differentiated osteoblasts and mineralizing bone matrix and therefore is suitable for subsequent in vivo implantation for regenerating segmental discontinuity bone defects.

Biological Responses of Ceramic Bone Spacers Produced by Green Processing of Additively Manufactured Thin Meshes

“…The material slightly stimulated early mineralization when compared to the control assessed using total ALP activity by absorbance values. These findings were in line with the literature on mineralization effect of β-TCP and hydroxyapatite studies [46,58]. The cells on the surface of the bone spacers stimulated bone-specific genes including Col 1, BGLAP, IBSP, and SSP1.…”

“…In the study conducted by Abel-Khattab et al [46], 3D silica containing calcium alkali orthophosphate scaffolds were manufactured by rapid prototyping and compared with scaffolds manufactured by Schwartzwalder Somers method (SSS) according to their mechanical properties and bioactivities. Scaffolds manufactured by rapid prototyping had more porosity than SSS and therefore silica release was much higher.…”

TomoPress—In Situ Synchrotron-Based Microtomography under Axial Load

“…The TomoPress is excellently suited to shed light on the mechanical properties of bone regenerated by using bone tissue engineering approaches. In this example we examined bioregenerated rat bone, that is, bone that was harvested from a large segmental defect in the rat femur which was regenerated using a tissue engineered synthetic bone graft-a 3D printed scaffold that contained homogenously distributed osteoblasts and mineralizing bone matrix upon implantation after seven days of in vitro perfusion cell culture prior to implantation [44].…”

Tissue engineering applications in otolaryngology—The state of translation

“…Heatmap representing the proportion of publications by year that utilized specific translational research methodologies from construct characterization to human trial to investigate craniofacial tissue engineering 49‐72,74‐77,79,81‐84,145‐197 …”