Remineralization of Demineralized Bone Matrixes with Preserved Fibrillary Structure as a Promising Approach to Obtain Highly Effective Osteoplastic Materials

The development of highly effective osteoplastic materials capable of providing bone tissue regeneration still remains an urgent and unresolved problem. In the presented work, an approach is proposed for the creation of biomimetic materials by the deposition of amorphous calcium phosphates on the surface of a xenogenic bone demineralized matrix under physiological conditions. Adsorption spectroscopy and scanning electron microscopy showed the efficiency of deposition of amorphous calcium phosphates on the trabeculae surface. The additional inclusion of the calcium-binding protein albumin was found to increase the efficiency of CPC adsorption on the trabeculae surface during DBM remineralization in vitro. In the model of heterotopic implantation for 7 weeks the osteoinductive properties of the obtained material were demonstrated, expressed in intrabecular mineralization of bone trabeculae, neovascularization and pronounced synthetic activity of osteoblasts (synthesis and structurization of neocollagen directly on the implanted material). The data obtained in the course of this work will be used to create new highly effective osteoplastic materials

Remineralization of Demineralized Bone Matrixes with Preserved Fibrillary Structure as a Promising Approach to Obtain Highly Effective Osteoplastic Materials

The development of highly effective osteoplastic materials capable of providing bone tissue regeneration still remains an urgent and unresolved problem. In the presented work, an approach is proposed for the creation of biomimetic materials by the deposition of amorphous calcium phosphates on the surface of a xenogenic bone demineralized matrix under physiological conditions. Adsorption spectroscopy and scanning electron microscopy showed the efficiency of deposition of amorphous calcium phosphates on the trabeculae surface. The additional inclusion of the calcium-binding protein albumin was found to increase the efficiency of CPC adsorption on the trabeculae surface during DBM remineralization in vitro. In the model of heterotopic implantation for 7 weeks the osteoinductive properties of the obtained material were demonstrated, expressed in intrabecular mineralization of bone trabeculae, neovascularization and pronounced synthetic activity of osteoblasts (synthesis and structurization of neocollagen directly on the implanted material). The data obtained in the course of this work will be used to create new highly effective osteoplastic materials

Composite Remineralization of Bone-Collagen Matrices by Low-Temperature Ceramics and Serum Albumin: A New Approach to the Creation of Highly Effective Osteoplastic Materials

This study examined the effectiveness of coating demineralized bone matrix (DBM) with amorphous calcium phosphate (DBM + CaP), as well as a composite of DBM, calcium phosphate, and serum albumin (DBM + CaP + BSA). The intact structure of DBM promotes the transformation of amorphous calcium phosphate (CaP) into dicalcium phosphate dihydrate (DCPD) with a characteristic plate shape and particle size of 5–35 µm. The inclusion of BSA in the coating resulted in a better and more uniform distribution of CaP on the surface of DBM trabeculae. MG63 cells showed that both the obtained forms of CaP and its complex with BSA did not exhibit cytotoxicity up to a concentration of 10 mg/mL in vitro. Ectopic (subcutaneous) implantation in rats revealed pronounced biocompatibility, as well as strong osteoconductive, osteoinductive, and osteogenic effects for both DBM + CaP and DBM + CaP + BSA, but more pronounced effects for DBM + CaP + BSA. In addition, for the DBM + CaP + BSA samples, there was a pronounced full physiological intrafibrillar biomineralization and proangiogenic effect with the formation of bone-morrow-like niches, accompanied by pronounced processes of intramedullary hematopoiesis, indicating a powerful osteogenic effect of this composite

Injectable Hydrated Calcium Phosphate Bone-like Paste: Synthesis, In Vitro, and In Vivo Biocompatibility Assessment

The injectable hydrated calcium phosphate bone-like paste (hCPP) was developed with suitable rheological characteristics, enabling unhindered injection through standard 23G needles. In vitro assays showed the cytocompatibility of hCPP with mesenchymal embryonic C3H10T1/2 cell cultures. The hCPP was composed of aggregated micro-sized particles with sphere-like shapes and low crystallinity. The ability of hCPP particles to adsorb serum proteins (FBS) was investigated. The hCPP demonstrated high protein adsorption capacity, indicating its potential in various biomedical applications. The results of the in vivo assay upon subcutaneous injection in Wistar rats indicated nontoxicity and biocompatibility of experimental hCPP, as well as gradual resorption of hCPP, comparable to the period of bone regeneration. The data obtained are of great interest for the development of commercial highly effective osteoplastic materials for bone tissue regeneration and augmentation

Low-Temperature Calcium Phosphate Ceramics Can Modulate Monocytes and Macrophages Inflammatory Response In Vitro

Creating bioactive materials for bone tissue regeneration and augmentation remains a pertinent challenge. One of the most promising and rapidly advancing approaches involves the use of low-temperature ceramics that closely mimic the natural composition of the extracellular matrix of native bone tissue, such as Hydroxyapatite (HAp) and its phase precursors (Dicalcium Phosphate Dihydrate—DCPD, Octacalcium Phosphate—OCP, etc.). However, despite significant scientific interest, the current knowledge and understanding remain limited regarding the impact of these ceramics not only on reparative histogenesis processes but also on the immunostimulation and initiation of local aseptic inflammation leading to material rejection. Using the stable cell models of monocyte-like (THP-1ATRA) and macrophage-like (THP-1PMA) cells under the conditions of LPS-induced model inflammation in vitro, the influence of DCPD, OCP, and HAp on cell viability, ROS and intracellular NO production, phagocytosis, and the secretion of pro-inflammatory cytokines was assessed. The results demonstrate that all investigated ceramic particles exhibit biological activity toward human macrophage and monocyte cells in vitro, potentially providing conditions necessary for bone tissue restoration/regeneration in the peri-implant environment in vivo. Among the studied ceramics, DCPD appears to be the most preferable for implantation in patients with latent inflammation or unpredictable immune status, as this ceramic had the most favorable overall impact on the investigated cellular models