Bone Repair and Regenerative Biomaterials: Towards Recapitulating the Microenvironment

Abstract

Biomaterials and tissue engineering scaffolds play a central role to repair bone defects. Although ceramic derivatives have been historically used to repair bone, hybrid materials have emerged as viable alternatives. The rationale for hybrid bone biomaterials is to recapitulate the native bone composition to which these materials are intended to replace. In addition to the mechanical and dimensional stability, bone repair scaffolds are needed to provide suitable microenvironments for cells. Therefore, scaffolds serve more than a mere structural template suggesting a need for better and interactive biomaterials. In this review article, we aim to provide a summary of the current materials used in bone tissue engineering. Due to the ever-increasing scientific publications on this topic, this review cannot be exhaustive; however, we attempted to provide readers with the latest advance without being redundant. Furthermore, every attempt is made to ensure that seminal works and significant research findings are included, with minimal bias. After a concise review of crystalline calcium phosphates and non-crystalline bioactive glasses, the remaining sections of the manuscript are focused on organic-inorganic hybrid materials.

3D Hierarchical, Nanostructured Chitosan/PLA/HA Scaffolds Doped with TiO2/Au/Pt NPs with Tunable Properties for Guided Bone Tissue Engineering

“…Their presence in many cases decreases sorption abilities of the hydrogels due to their interactions with functional groups. In the case of proposed supporting tissue-regeneration materials, all of them exhibited SC above 200%, meaning that they are suitable for bone recovery [1,5,6]. High sorption ability is especially important during the biomineralization process, which significantly hampers water absorption by hydrogels [41].…”

“…To determine morphological properties of the scaffolds, as well as their semi-components, their structure was analyzed by SEM and TEM microscopy. Figure 7a shows pure crosslinked chitosan aerogel, which has a highly porous structure, with pores dimension in the range between 100 and 500 µm, thus providing appropriate conditions for osteoblasts growth, proliferation, and osteogenesis process meeting requirements for bone-tissue engineering [1,5,6]. The scaffold was further modified with synthetic hydroxyapatite, to increase its affinity to this type of tissue and bioactivity (Figure 7b).…”

“…Additionally, in contrast to silver nanoparticles [28], they are characterized by very good chemical stability and are known to disarm reactive oxygen species (ROS), which may have a positive effect on cells' proliferation, since they prevent their apoptosis triggered by oxygen radicals [25][26][27]31]. Lack of scaffolds' toxicity can be also assigned to the well-known biosafety of semi-components, such as chitosan [34][35][36] and PLA [2][3][4][5][6][7], which are widely used for bone-tissue regeneration [38]. Moreover, the scaffolds' architecture seems to provide good conditions for cells' growth and do not hamper their natural behaviors [38].…”

“…Porous materials can be embedded with various substances which promote osteoconduction. The ideal scaffold for this application should meet five conditions, namely biocompatibility, biodegradability, bioactivity, appropriate architecture, and high durability [4][5][6][7][8].…”

Covalent Surface Functionalization of Bovine Serum Albumin to Magnesium Surface: Enhancing Robust Corrosion Inhibition and In vitro Osteo-Inductivity

“…The implantable scaffolds that can inherit a remarkable biological and physiological bio-interface to host stem cells are rapidly expanding their applications towards clinical studies in bone tissue engineering [1,2]. Such scaffolds have tendency to acquire biomimetic behavior akin to those of native host tissue for absorbing proteins, biominerals and interacting with extracellular matrix (ECM) [3]. Importantly, the biomimetic scaffolds are liable to complement in wound healing system or tissue engineering which leads to restore tissue functions, enhance stem/progenitor cells regeneration, and regulate the delivery of the cells growth factors and cytokines [4].…”