Tendon‐to‐bone interface has a hierarchical structure and gradient component that are conducive to distributing the stresses to achieve movement. Conventional biomaterials lack the capacity to induce synchronous repair of multiple tissues, resulting in the failure of the interface repair. Biomimetic strategies have attracted enormous attention in the field of complex structure regeneration because they can meet the different physiological requirements of multiple tissues. Herein, a biomimetic ink mimicking tendon/bone tissues is developed by combining tendon/bone‐related cells and Mo‐containing silicate (MS) bioceramics. Subsequently, biomimetic multicellular scaffolds are fabricated to achieve the simulation of the hierarchical structure and cellular composition of tendon‐to‐bone interfaces by the spatial distribution of the biomimetic inks via 3D bioprinting, which is of great significance for inducing the regeneration of complex structures in the interface region. In addition, attributed to the desirable ionic microenvironment created by MS bioceramics, the biomimetic scaffolds possess the dual function of inducing tendon/bone‐related cells tenogenic and osteogenic differentiation in vitro, and promote the integrated regeneration of tendon‐to‐bone interfaces in vivo. The study offers a feasible strategy to construct biomimetic multicellular scaffolds with bifunction for inducing multi‐lineage tissue regeneration, especially for regenerating soft‐to‐hard tissue interfaces.
1 October 2017 in Materials Science and Engineering: C
Although calcium phosphate cements (CPCs) have been clinically used to repair bone defects caused by bone tumor resection, traditional CPCs cannot kill the remaining tumor cells after surgery and prevent cancer recurrence. In this study, a multifunctional injectable metal–organic framework (MOF) cobalt coordinated tetrakis(4-carboxyphenyl)porphyrin (Co-TCPP)-modified calcium phosphate cement (Co-TCPP/CPC) was prepared for the minimally invasive treatment of neoplastic bone defects. The incorporation of Co-TCPP not only retained the good injectability of bone cements, but also shortened the setting time, improved the compressive strength, and endowed them with excellent photothermal properties. The hyperthermia effect induced by the presence of Co-TCPP well induced the therapeutic effect against bone tumors both in vitro and in vivo. Moreover, Co-TCPP/CPC exhibited desirable osteogenesis and angiogenesis by promoting bone and vascular regeneration in vivo. Therefore, the Co-TCPP composite bone cement demonstrated its great potential for bone tumor therapy and tissue regeneration, representing a multifunctional biomaterial for the treatment of neoplastic bone defects.
Iron-matrix composites with calcium silicate (CS) bioceramic as the reinforcing phase were fabricated through powder metallurgy processes. The microstructures, mechanical properties, apatite deposition and biodegradation behavior of the Fe-CS composites, as well as cell attachment and proliferation on their surfaces, were characterized. In the range of CS weight percentages selected in this study, the composites possessed compact structures and showed differently decreased bending strengths as compared with pure iron. Immersion tests in simulated body fluid (SBF) revealed substantially enhanced deposition of CaP on the surfaces of the composites as well as enhanced degradation rates as compared with pure iron. In addition, the composite containing 20% CS showed a superior ability to stimulate hBMSCs proliferation when compared to pure iron. Our results suggest that incorporating calcium silicate particles into iron could be an effective approach to developing iron-based biodegradable bone implants with improved biomedical performance.
1 July 2018 in Materials Science and Engineering: C
Porous Ti-6Al-4V scaffolds fabricated by means of selective laser melting (SLM), having controllable geometrical features and preferable mechanical properties, have been developed as a class of biomaterials that hold promising potential for bone repair. However, the inherent bio-inertness of the Ti-6Al-4V alloy as the matrix of the scaffolds results in a lack in the ability to stimulate bone ingrowth and regeneration. The aim of the present study was to develop a bioactive coating on the struts of SLM Ti-6Al-4V scaffolds in order to add the desired surface osteogenesis ability. Mesoporous bioactive glasses (MBGs) coating was applied on the strut surfaces of the SLM Ti-6Al-4V scaffolds through spin coating, followed by a heat treatment. It was found that the coating could maintain the characteristic mesoporous structure and chemical composition of MBG, and establish good interfacial adhesion to the Ti-6Al-4V substrate. The compressive strength and pore interconnectivity of the scaffolds were not affected by the coating. Moreover, the results obtained from in vitro cell culture experiments demonstrated that the attachment, proliferation, and differentiation of human bone marrow stromal cells (hBMSCs) on the MBG-coated Ti-6Al-4V scaffolds were improved as compared with those on the conventional bioactive glass (BG)-coated Ti-6Al-4V scaffolds and bare-metal Ti-6Al-4V scaffolds. Our results demonstrated that the MBG coating by using the spinning coating method could be an effective approach to achieving enhanced surface biofunctionalization for SLM Ti-6Al-4V scaffolds.