Injectable chelate-setting hydroxyapatite cement prepared by using chitosan solution: Fabrication, material properties, biocompatibility, and osteoconductivity

Magnesium (Mg2 +), Strontium (Sr2 +), and Zinc (Zn2 +) Co-substituted Bone Cements Based on Nano-hydroxyapatite/Monetite for Bone Regeneration

New bone cement type that combines Sr2 + /Mg2 + or Sr2 + /Zn2 + co-substituted nano-hydroxyapatite (n-HAs) with calcium phosphate dibasic and chitosan/gelatin polymers was developed to increase adhesion and cellular response. The cements were physicochemically described and tested in vitro using cell cultures. All cements exhibited quite hydrophilic and had high washout resistance. Cement releases Ca2 + , Mg2 + , Sr2 + , and Zn2 + in concentrations that are suitable for osteoblast proliferation and development. All of the cements stimulated cell proliferation in fibroblasts, endothelial cells, and osteoblasts, were non-cytotoxic, and produced apatite. Cements containing co-substituted n-HAs had excellent cytocompatibility, which improved osteoblast adhesion and cell proliferation. These cements had osteoinductive potential, stimulating extracellular matrix (ECM) mineralization and differentiation of MC3T3-E1 cells by increasing ALP and NO production. The ions Ca2 + , Mg2 + , Zn2 + , and Sr2 + appear to cooperate in promoting osteoblast function. The C3 cement (HA-SrMg5%), which was made up of n-HA co-substituted with 5 mol% Sr and 5 mol% Mg, showed exceptional osteoinductive capacity in terms of bone regeneration, indicating that this new bone cement could be a promising material for bone replacement.

In vivo mimicking injectable self-setting composite bio-cement: Scanning acoustic diagnosis and biological property evaluation for tissue engineering applications

Injectability and self-setting properties are important factors to increase the efficiency of bone regeneration and reconstruction, thereby reducing the invasiveness of hard tissue engineering procedures. In this study, 63S bioactive glass (BG), nano-hydroxyapatite (n-HAp), alumina, titanium dioxide, and methylene bis-acrylamide (MBAM)-mediated polymeric crosslinking composites were prepared for the formulation of an efficient self-setting bone cement. According to the cytocompatibility and physicochemical analyses, all the samples qualified the standard of the bio-composite materials. They revealed high thermal stability, injectability, and self-setting ability supported by ~ 10.73% (maximum) mass loss, ~ 92-93% injectability and 24 ± 5 min of initial setting time. Moreover, a cellular adhesion and proliferation study was additionally performed with osteoblasts like MG-63 cells, which facilitate pseudopod-like cellular extensions on the BG/n-HAp composite scaffold surface. The SAM study was employed to non-invasively assess the self-setting properties of the composite bio-cement using the post injected distribution and physical properties of the phantom. These results validate the significant potential characteristics of the BG/n-HAp self-setting bio-cement (16:4:2:1) for promising minimal-invasive bone tissue engineering applications.

Recent Advances in Biomaterials for the Treatment of Bone Defects

Bone defects or fractures generally heal in the absence of major interventions due to the high regenerative capacity of bone tissue. However, in situations of severe/large bone defects, these orchestrated regeneration mechanisms are impaired. With advances in modern medicine, natural and synthetic bio-scaffolds from bioceramics and polymers that support bone growth have emerged and gained intense research interest. In particular, scaffolds that recapitulate the molecular cues of extracellular signals, particularly growth factors, offer potential as therapeutic bone biomaterials. The current challenges for these therapies include the ability to engineer materials that mimic the biological and mechanical properties of the real bone tissue matrix, whilst simultaneously supporting bone vascularization. In this review, we discuss the very recent innovative strategies in bone biomaterial technology, including those of endogenous biomaterials and cell/drug delivery systems that promote bone regeneration. We present our understanding of their current value and efficacy, and the future perspectives for bone regenerative medicine.

NGF-CS/HA-coating composite titanium facilitates the differentiation of bone marrow mesenchymal stem cells into osteoblast and neural cells

Dental implant is the most effective way to repair the defect or absence of dentition. Currently, the modification in titanium surface properties has become a hot topic in the study of oral implantology. However, more suitable titanium surface coating still needs to be further explored. We prepared the nerve growth factor-chondroitin sulfate/hydroxyapatite (NGF-CS/HA)-coating composite titanium by modified biomimetic method. We also observed the surface morphology, thickness, surface adhesion and component analysis of NGF-CS/HA-coating composite titanium by scanning electron microscope, and the release of NGF was also identified via ELISA assay. Besides, the identification of bone marrow mesenchymal stem cells (BMSCs) was conducted through alizarin red staining, oil red O staining and fluorescence detection. and the osteogenesis differentiation and neuronal differentiation-related genes were determined by RT-qPCR assay. The surface of NGF-CS/HA coating with the 65.4 ± 6.4 μm thickness presented a porous network, and the main components of NGF-CS/HA coating were Ti and HA, and maintained the activity and release of NGF. Besides, we successfully obtained and identified BMSCs, and proved that NGF-CS/HA-coating composite titanium could notably upregulated the expression levels of the osteogenesis differentiation and neuronal differentiation-related genes and proteins in BMSCs. In conclusion, NGF-CS/HA-coating composite titanium has significant promoting effects on the differentiation of BMSCs into osteoblast and neural cells.