Advances on Bone Substitutes through 3D Bioprinting

Abstract

Reconstruction of bony defects is challenging when conventional grafting methods are used because of their intrinsic limitations (biological cost and/or biological properties). Bone regeneration techniques are rapidly evolving since the introduction of three-dimensional (3D) bioprinting. Bone tissue engineering is a branch of regenerative medicine that aims to find new solutions to treat bone defects, which can be repaired by 3D printed living tissues. Its aim is to overcome the limitations of conventional treatment options by improving osteoinduction and osteoconduction. Several techniques of bone bioprinting have been developed: inkjet, extrusion, and light-based 3D printers are nowadays available. Bioinks, i.e., the printing materials, also presented an evolution over the years. It seems that these new technologies might be extremely promising for bone regeneration. The purpose of the present review is to give a comprehensive summary of the past, the present, and future developments of bone bioprinting and bioinks, focusing the attention on crucial aspects of bone bioprinting such as selecting cell sources and attaining a viable vascularization within the newly printed bone. The main bioprinters currently available on the market and their characteristics have been taken into consideration, as well.

Comparison of the Translational Potential of Human Mesenchymal Progenitor Cells from Different Bone Entities for Autologous 3D Bioprinted Bone Grafts

“…For the successful clinical implementation of cell-containing 3D bioprinted bone constructs, selecting the right cell source is essential [ 13 , 14 , 15 , 16 ]. The cell source should ideally combine low morbidity of the initial biopsy, an easy harvesting method, rapid expansion, and the ability to differentiate into bone-forming cells [ 16 ].…”

“…The cell source should ideally combine low morbidity of the initial biopsy, an easy harvesting method, rapid expansion, and the ability to differentiate into bone-forming cells [ 16 ]. Mesenchymal stem or progenitor cells (MPCs) can be isolated from different body tissues and extensively expanded in vitro while maintaining their undifferentiated, multipotent condition, and have already been investigated in clinical trials [ 13 , 17 ]. MPCs derived from bone marrow and adipose tissue are the ones that have mainly been used for bioprinting artificial bone tissue [ 13 , 16 , 18 ].…”

“…Mesenchymal stem or progenitor cells (MPCs) can be isolated from different body tissues and extensively expanded in vitro while maintaining their undifferentiated, multipotent condition, and have already been investigated in clinical trials [ 13 , 17 ]. MPCs derived from bone marrow and adipose tissue are the ones that have mainly been used for bioprinting artificial bone tissue [ 13 , 16 , 18 ]. However, the possibility of failure of cell extraction and the inconsistent tissue ossification and speed are barriers to using this procedure in a clinical setting [ 19 , 20 ].…”

Nanoscale Topographies for Corneal Endothelial Regeneration

“…Micrometer scale and nanometer scale topographies' (microtopographies and nanotopographies') structures on cell culture surfaces have been shown to modulate cell behavior, for example by increasing cell adhesion, proliferation, migration, survival, differentiation and phenotype maintenance in many applications [17,[19][20][21][22]. The addition of instructive topographies on cell culture scaffolds could, therefore, provide significant advantages compared to conventional flat (smooth) 2D substrates, as the first can offer biophysical cues that more closely replicate those present in the native ECM.…”

The Glycoprotein/Cytokine Erythropoietin Promotes Rapid Alveolar Ridge Regeneration In Vivo by Promoting New Bone Extracellular Matrix Deposition in Conjunction with Coupled Angiogenesis/Osteogenesis

“…Bone is a highly vascularized tissue [ 8 ]. During bone development, bone mineralization is tightly coupled with angiogenesis [ 9 ].…”