Bone Tissue Engineering Scaffolds: Function of Multi‐Material Hierarchically Structured Scaffolds

Abstract

Bone tissue engineering (BTE) is a topic of interest for the last decade, and advances in materials, processing techniques, and the understanding of bone healing pathways have opened new avenues of research. The dual responsibility of BTE scaffolds in providing load‐bearing capability and interaction with the local extracellular matrix to promote bone healing is a challenge in synthetic scaffolds. This article describes the usage and processing of multi‐materials and hierarchical structures to mimic the structure of natural bone tissues to function as bioactive and load‐bearing synthetic scaffolds. The first part of this literature review describes the physiology of bone healing responses and the interactions at different stages of bone repair. The following section reviews the available literature on biomaterials used for BTE scaffolds followed by some multi‐material approaches. The next section discusses the impact of the scaffold's structural features on bone healing and the necessity of a hierarchical distribution in the scaffold structure. Finally, the last section of this review highlights the emerging trends in BTE scaffold developments that can inspire new tissue engineering strategies and truly develop the next generation of synthetic scaffolds.

Recent Advancements in Design Optimization of Lattice‐Structured Materials

“…The study suggests exploring the impact absorption and dynamic compression behavior of the biphasic structures. Besides, Diamantopoulou et al [106] synthesized a biphasic (i.e., bimaterial) primitive structure composed of a polymeric core and ceramic (alumina) skins, where the weight fraction of the latter was varied from 0% (pure polymer) to 100% (pure ceramic). It turned out that the Young's moduli of the proposed sandwich constructions increased monotonically with increasing alumina weight fraction, while the highest SEA (i.e., 3.36 J g À1 ) was attained with the 40%wt alumina construction.…”

Superiority of Triply Periodic Minimal Surface Gyroid Structure to Strut-Based Grid Structure in Both Strength and Bone Regeneration

“…Primitive properties such as the presence or absence of osteoconductivity are influenced by the chemical composition of the scaffold. − Calcium phosphate is an osteoconductive material. , Carbonate apatite, which is a bone mineral, has favorable osteoconductivity among various calcium phosphates such as hydroxyapatite and tricalcium phosphate, and it is resorbed by osteoclasts and replaced with new bone. , However, the chemical composition of a scaffold is merely one factor, and in most cases, the porous structure or pore geometry has a greater effect on bone regeneration. − …”

“…The importance of pore connectivity in scaffolds for bone regeneration is widely recognized. − A structure with high pore connectivity includes a honeycomb structure with continuous uniaxial pores, i.e., channels. ,,− Previous studies demonstrated that honeycomb scaffolds with an adequate channel aperture (∼300 μm) can prevent the intrusion of soft tissues around a bone defect and guide only bone into the scaffold. − A comparison with previous studies revealed that honeycomb scaffolds show superior osteogenesis and angiogenesis in three-dimensional (3D) porous scaffolds. − …”

The Development of Naringin for Use against Bone and Cartilage Disorders

“…Researchers are interested in the potential efficacy of synthetic and/or natural compounds against bone and cartilage disorders [3,4]. Tofacitinib, a Janus kinase inhibitor, is a disease-modifying anti-rheumatic drug (DMARDs) and shows therapeutic effects against rheumatoid arthritis (RA).…”