Advanced Strategies of Biomimetic Tissue‐Engineered Grafts for Bone Regeneration

Abstract

The failure to repair critical-sized bone defects often leads to incomplete regeneration or fracture non-union. Tissue-engineered grafts have been recognized as an alternative strategy for bone regeneration due to their potential to repair defects. To design a successful tissue-engineered graft requires the understanding of physicochemical optimization to mimic the composition and structure of native bone, as well as the biological strategies of mimicking the key biological elements during bone regeneration process. This review provides an overview of engineered graft-based strategies focusing on physicochemical properties of materials and graft structure optimization from macroscale to nanoscale to further boost bone regeneration, and it summarizes biological strategies which mainly focus on growth factors following bone regeneration pattern and stem cell-based strategies for more efficient repair. Finally, it discusses the current limitations of existing strategies upon bone repair and highlights a promising strategy for rapid bone regeneration.

Radially Porous Nanocomposite Scaffolds with Enhanced Capability for Guiding Bone Regeneration In Vivo

“…[17] Previous studies have certified that scaffolds with oriented porous structure are more favorable for infiltration and migration of surrounding cells, exchange of nutrients and wastes, and also deposition of extracellular matrix, compared with scaffolds with random porous structure. [18][19][20] Among a variety of methods, [2,3] the burgeoning 3D printing [21,22] and directional freeze-casting techniques [23,24] are the most powerful approaches to engineer TE scaffolds with oriented porous structure, which both have their own advantages. 3D printing, for example, can spatially control the structure and composition of scaffolds to an unprecedented degree.…”

Bioactive Scaffolds Integrated with Liposomal or Extracellular Vesicles for Bone Regeneration

“…As several bioactive molecules including growth factors, nucleic acids, peptides, and small molecules have been demonstrated to play important roles in regulating cellular activities and bone tissue development, numerous studies have applied bioactive molecules into the BTE scaffolds [6]. Nonetheless, successful delivery of bioactive molecules at the bone defect site has been hampered due to a lack of proper delivery systems, giving rise to fast degradation, burst release, and non-specific targeting of bioactive molecules [7,8]. Accordingly, the regenerative performance of current BTE scaffolds requires improvement for clinical practice, urging need for the development of efficient bioactive molecule delivery systems.…”

Design of 3D Scaffolds for Hard Tissue Engineering: From Apatites to Silicon Mesoporous Materials

“…However, considering the composition of bones, HA combined with other polymeric components, such as collagen, gelatin, diverse polysaccharide, etc., would be the ideal material to use in bone tissue engineering [63][64][65][66][67]. Among the polymers, both natural and synthetic hydrogels present many similarities with the macroscopic macromolecular components of the extracellular matrix of living beings [68,69].…”