Mg-based Scaffolds Research Articles

Analysis of the CPZ/Wnt4 osteogenic pathway for high-bonding-strength composite-coated magnesium scaffolds through transcriptomics

Magnesium (Mg)-based scaffolds are garnering increasing attention as bone repair materials owing to their biodegradability and mechanical resemblance to natural bone. Their effectiveness can be augmented by incorporating surface coatings to meet clinical needs. However, the limited bonding strength and unclear mechanisms of these coatings have impeded the clinical utility of scaffolds. To address these issues, this study introduces a composite coating of high-bonding-strength polydopamine-microarc oxidation (PDA-MHA) on Mg-based scaffolds. The results showed that the PDA-MHA coating achieved a bonding strength of 40.56 ± 1.426 MPa with the Mg scaffold surface, effectively enhancing hydrophilicity and controlling degradation rates. Furthermore, the scaffold facilitated bone regeneration by influencing osteogenic markers such as RUNX-2, OPN, OCN, and VEGF. Transcriptomic analyses further demonstrated that the PDA-MHA/Mg scaffold upregulated carboxypeptidase Z expression and activated the Wnt-4/β-catenin signaling pathway, thereby promoting bone regeneration. Overall, this study demonstrated that PDA can synergistically enhance bone repair with Mg scaffold, broadening the application scenarios of Mg and PDA in the field of biomaterials. Moreover, this study provides a theoretical underpinning for the application and clinical translation of Mg-based scaffolds in bone tissue engineering endeavors.

Mg alloy scaffold with spherical/cubic hybrid pores for orthopedic repair

Biodegradable Mg-based scaffolds are regarded as potential bone tissue engineering materials for a promising approach to bone repair. In this work, the spherical/cubic hybrid pore-forming agents were introduced to prepare a porous Mg-based alloy scaffold by the negative salt pattern molding method. The porous Mg-Zn-Ca alloy scaffold containing spherical/cubic hybrid pores exhibited a porosity of about 68.60 % and a surface area ratio of about 7.88 cm2/cm3. The compressive elastic modulus was about 0.32 GPa and the compressive strength was about 4.22 MPa, close to cancellous bone. However, the rapid degradation of Mg alloy scaffold was inadaptive to orthopedic repair. Thus, a calcium phytate coating was prepared on the Mg-based scaffold for surface modification to retard rapid corrosion.

Porous Mg–Zn–Ca scaffolds for bone repair: a study on microstructure, mechanical properties and in vitro degradation behavior

Biodegradable porous Mg scaffolds are a promising approach to bone repair. In this work, 3D-spherical porous Mg–1.5Zn–0.2Ca (wt.%) scaffolds were prepared by vacuum infiltration casting technology, and MgF2 and fluorapatite coatings were designed to control the degradation behavior of Mg-based scaffolds. The results showed that the pores in Mg-based scaffolds were composed of the main spherical pores (450–600 μm) and interconnected pores (150–200 μm), and the porosity was up to 74.97%. Mg-based porous scaffolds exhibited sufficient mechanical properties with a compressive yield strength of about 4.04 MPa and elastic modulus of appropriately 0.23 GPa. Besides, both MgF2 coating and fluorapatite coating could effectively improve the corrosion resistance of porous Mg-based scaffolds. In conclusion, this research would provide data support and theoretical guidance for the application of biodegradable porous Mg-based scaffolds in bone tissue engineering.Graphical

Immobilization of bioactive vascular endothelial growth factor onto Ca-deficient hydroxyapatite-coated Mg by covalent bonding using polydopamine.

BackgroundBone tissue engineering (BTE) is considered a promising technology for repairing bone defects. Mg2+ promotes osteogenesis, which makes Mg-based scaffolds popular for research on orthopedic implant materials. Angiogenesis plays an important role in the process of bone tissue repair and regeneration, and it is one of the important problems in BTE urgently needs to be solved.MethodsMg was firstly coated with Ca-deficient hydroxyapatite (CDHA) via hydrothermal treatment, and polydopamine (DOPA) was then used as the connecting medium to immobilize vascular endothelial growth factor (VEGF) on the CDHA coating. The physicochemical properties of the coatings were characterized by SEM, EDS, XPS, FTIR and immersion experiment in SBF. The ahesion, proliferation, and angiogenesis potential of the coatings were determined in vitro.ResultsThe composite coating significantly improved the corrosion resistance of Mg and prohibited excessively high local alkalinity. VEGF could be firmly immobilized on Mg via polydopamine. The CCK-8, live/dead staining and adhesion test results showed that the VEGF-DOPA-CDHA coating exhibited excellent biocompatibility and could significantly improve the adhesion and proliferation of MC3T3-E1 cells on Mg. Microtubule formation, immunofluorescence and Quantitative Real-Time PCR (qRT-PCR) experiments showed that VEGF immobilized on Mg still possessed bioactivity in promoting the differentiation of rat mesenchymal stem cells into endothelial cells.ConclusionIn this study, we enabled the angiogenic biological activity of Mg by immobilizing VEGF on Mg. Mg was successfully coated with a functional VEGF-DOPA-CDHA composite coating. The CDHA coating significantly increased the corrosion resistance of Mg and prohibited the negative effect of excessively high local alkalinity on the biological activity of VEGF. As an intermediate layer, the DOPA coating protects Mg, and DOPA provides a binding site for VEGF so that VEGF can be firmly immobilized on Mg and give Mg angiogenic bioactivity during the initial period of implantation.The translational potential of this articleThe treatment of large bone defect is still one of the orthopedic trauma diseases that are difficult to be completely treated in clinic. The development of tissue engineering technology provides a new option for the treatment of large bone defects. The regeneration of blood vessels is of great significance for the repair of bone defects. In this study, VEGF was connected on the surface of degradable magnesium by covalent bonding. Vascular biofunctionalized magnesium scaffolds are expected to regenerate bone tissue with blood transport and be used in the clinical treatment of large bone defects.

Multi-scale mechanical and morphological characterisation of sintered porous magnesium-based scaffolds for bone regeneration in critical-sized defects

Magnesium (Mg) and its alloys are very promising degradable, osteoconductive and osteopromotive materials to be used as regenerative treatment for critical-sized bone defects. Under load-bearing conditions, Mg alloys must display sufficient morphological and mechanical resemblance to the native bone they are meant to replace to provide adequate support and enable initial bone bridging. In this study, unique highly open-porous Mg-based scaffolds were mechanically and morphologically characterised at different scales. In situ X-ray computed tomography (XCT) mechanics, digital volume correlation (DVC), electron microscopy and nanoindentation were combined to assess the influence of material properties on the apparent (macro) mechanics of the scaffold. The results showed that Mg exhibited a higher connected structure (38.4mm−3 and 6.2mm−3 for Mg and trabecular bone (Tb), respectively) and smaller spacing (245µm and 629µm for Mg and Tb, respectively) while keeping an overall appropriate porosity of 55% in the range of trabecular bone (30-80%). This fully connected and highly porous structure promoted lower local strain compared to the trabecular bone structure at material level (i.e. -22067 ± 8409µε and -40120 ± 18364µε at 6% compression for Mg and trabecular bone, respectively) and highly ductile mechanical behaviour at apparent level preventing premature scaffold failure. Furthermore, the Mg scaffolds exceeded the physiological strain of bone tissue generated in daily activities such as walking or running (500-2000µε) by one order of magnitude. The yield stress was also found to be close to trabecular bone (2.06MPa and 6.67MPa for Mg and Tb, respectively). Based on this evidence, the study highlights the overall biomechanical suitability of an innovative Mg-based scaffold design to be used as a treatment for bone critical-sized defects. Statement of significanceBone regeneration remains a challenging field of research where different materials and solutions are investigated. Among the variety of treatments, biodegradable magnesium-based implants represent a very promising possibility. The novelty of this study is based on the characterisation of innovative magnesium-based implants whose structure and manufacturing have been optimised to enable the preservation of mechanical integrity and resemble bone microarchitecture. It is also based on a multi-scale approach by coupling high-resolution X-ray computed tomography (XCT), with in situ mechanics, digital volume correlation (DVC) as well as nano-indentation and electron-based microscopy imaging to define how degradable porous Mg-based implants fulfil morphological and mechanical requirements to be used as critical bone defects regeneration treatment.

Tailoring adaptive bioresorbable Mg-based scaffolds with directed plasma nanosynthesis for enhanced osseointegration and tunable resorption

Directed plasma nanosynthesis (DPNS) is a plasma-based surface modification process used to provide high-fidelity bioactive and bioresorbable interfaces for Mg-based foams having an average 500-μm pore size and containing main components of Al, Zn and Ca at bal., 3.3%, 1.11%, and 0.21%, respectively. Correlations of incident particle energies of 400–700 eV and room temperature, normal and off-normal incidence angles of 0° and 60°, respectively, and high-ion fluence conditions are combined to elicit a bioreactive Mg-foam surface. H2 evolution and pH levels of irradiated and non-irradiated Mg-foams were examined and correlated to the DPNS parameters. In situ X-ray photoelectron spectroscopy and focused ion-beam results have shown that energies of ~ 400–700 eV can control surface topography and composition, which, in turn, controls the foam-corrosion mechanism. Samples are immersed in Dulbecco’s modified eagle media, and a synergistic reaction is found in which the irradiated samples enhance the formation of calcium–phosphate (CaP) phases to CaP ratios close to the hydroxylapatite phase that enhances bone-tissue regeneration. These results lead to a surface modification strategy that adjusts the interaction of the material and the environment without using a coating that could affect the geometry and the bulk properties of the porous material.

Surface Modification of Biodegradable Mg-Based Scaffolds for Human Mesenchymal Stem Cell Proliferation and Osteogenic Differentiation.

Magnesium alloys with coatings have the potential to be used for bone substitute alternatives since their mechanical properties are close to those of human bone. However, the surface modification of magnesium alloys to increase the surface biocompatibility and reduce the degradation rate remains a challenge. Here, FHA-Mg scaffolds were made of magnesium alloys and coated with fluorohydroxyapatite (FHA). Human mesenchymal stem cells (hMSCs) were cultured on FHA-Mg scaffolds and cell viability, proliferation, and osteogenic differentiation were investigated. The results showed that FHA-Mg scaffolds display a nano-scaled needle-like structure of aggregated crystallites on their surface. The average Mg2+ concentration in the conditioned media collected from FHA-Mg scaffolds (5.8–7.6 mM) is much lower than those collected from uncoated, Mg(OH)2-coated, and hydroxyapatite (HA)-coated samples (32.1, 17.7, and 21.1 mM, respectively). In addition, compared with hMSCs cultured on a culture dish, cells cultured on FHA-Mg scaffolds demonstrated better proliferation and comparable osteogenic differentiation. To eliminate the effect of osteogenic induction medium, hMSCs were cultured on FHA-Mg scaffolds in culture medium and an approximate 66% increase in osteogenic differentiation was observed three weeks later, indicating a significant effect of the nanostructured surface of FHA-Mg scaffolds on hMSC behaviors. With controllable Mg2+ release and favorable mechanical properties, porous FHA-Mg scaffolds have a great potential in cell-based bone regeneration.

3D-cubic interconnected porous Mg-based scaffolds for bone repair

Abstract Mg-based porous materials, as potential bone tissue engineering scaffolds, are considered an attractive strategy for bone repair owing to favorable biodegradability, good biocompatibility and suitable mechanical properties. In this work, 3D-cubic interconnected porous Mg–xZn–0.3Ca (x = 0,3,6) scaffolds were prepared to obtain desirable pore structures with a mean porosity up to 73% and main pore size of 400–500 µm, which pore structures were close to the human cancellous bone. The structure–property relationships in the present scaffolds were analyzed by experiments and theoretical models of generalized method of cells (GMC). Mg–xZn–0.3Ca scaffolds exhibited good compression properties with a maximum above 5 MPa in yield strength and about 0.4 GPa in elastic modulus. This was attributed to not only the alloy strengthening but also the large minimum solid area. On the other hand, the scaffolds showed undesirable and relatively serious degradation behavior in Hank's solution, resulting from Zn addition in Mg-based scaffolds and the high surface area ratio in the pore structure. Therefore, surface modifications are worth studying for controlled degradation in the future. In conclusion, this research would explore a novel attempt to introduce 3D-cubic pore structure for Mg-based scaffolds, and provide new insights into the preparations of Mg-based scaffolds with good service performances for bone repair.

Simultaneous enhancement of anti-corrosion, biocompatibility, and antimicrobial activities by hierarchically-structured brushite/Ag3PO4-coated Mg-based scaffolds.

Development of bone graft substitutes with appropriate integration of mechanical, biodegradable, and biofunctional properties, which promote bone formation while simultaneously preventing implant-associated infections, remains a great challenge. Herein we designed and synthesized a brushite/Ag3PO4-coated Mg-Nd-Zn-Zr scaffolds through chemical solution deposition of a composite coating onto the fluorinated Mg-based scaffolds generated with template replication method. The coated Mg-based open-porous scaffolds exhibit hierarchically-structured surface with cube-shaped Ag3PO4 nanoparticles uniformly distributed on top of microsized brushite grains. Immersion test reveals that the initial degradation rate of the coated scaffolds could be reduced by ~81% compared to the original scaffolds. The mean corrosion rate in 4weeks falls into 0.10-0.15mm/year to meet clinical requirements. The compatibility and ALP activity of cells grown in the extracts from the coated Mg-based scaffolds were increased compared with Ti control and original scaffolds, mainly due to the favorable microenvironment generated by Mg biodegradation. Besides, the coated Mg-based scaffold demonstrated potent antimicrobial activity via the synergistic actions of alkaline degradation products of Mg and the Ag species in the coating, achieving >99.5% antibacterial rate against both gram-positive and gram-negative bacteria with relatively low silver content. Taken together, this study presents a new candidate of brushite/Ag3PO4-coated Mg-based scaffold with appropriate degradation characteristics, cytocompatibility, and antimicrobial activities for bone tissue engineering applications.

The in vitro and in vivo biological effects and osteogenic activity of novel biodegradable porous Mg alloy scaffolds

Inspired by the process of bone reconstruction, porous scaffolds with robust osteogenesis and biodegradability would provide an ideal bone substitute for clinical practice. In this study, a novel porous Mg–Nd–Zn–Zr (JDBM) alloy scaffold coated with brushite (i.e., DCPD), denoted as JDBM-DCPD, is fabricated using a special patent template technique, which forms the main spherical pores (400–450 μm) and smaller pores (150–250 μm) interconnected between the adjacent main pores, facilitating nutrient penetration and cell in-growth, exhibiting sufficient mechanical properties. In vitro results demonstrate that JDBM-DCPD scaffolds promote cell in-growth and osteogenic differentiation, which significantly enhance mineralization, osteogenesis and angiogenesis-related genes expression when cultured with bone marrow mesenchymal stem cells. After implanting in vivo, JDBM-DCPD scaffolds effectively stimulate angiogenesis, osteogenesis, and remodeling with the degradation of JDBM-DCPD, and perfectly repair large bone defect in rat and rabbit models. Results from the present study provide the solid evidence that porous biodegradable Mg-based scaffolds whose pore structure can be precisely regulated by a spacer-selection technique may be a promising tissue engineering scaffolds for large bone defect repair clinically, free from any extra growth factors and live cells, such advances will make scaffold-based bone tissue repair safer, more convenient and more cost-effective.

Synthesis and Properties of Mg-Based Foams by Infiltration Casting Without Protective Cover Gas

Fabrication and characterization of Mg-based scaffolds by infiltration casting, without protective cover gas, are presented. Distinctive results were observed among the foams depending on the precise selection of casting variables. Foams with pore sizes ranging from 590 to 1040 µm, porosities ranging from 60.01 to 79.35%, and measured Young’s moduli ranging from 0.8 to 1.9 GPa, were obtained. These architected parameters for this cellular material were found to match the structural properties of cancellous bone while satisfying the mechanical requirements to support the bone healing process (0.3-3 GPa). Casting temperature and melting time were set at 680 °C and 10 min for infiltrating 590 µm salt particles. A salt flux combination containing MgCl2, MgO, CaF2, and KCl, is used to protect the molten metal, and its effect on ignition and oxidation of the Mg alloy is evaluated. The results of the crystalline phase and chemical analysis indicate a safe production process since there is no evidence of high contamination or new-formed phases.

Synthesis and in-vitro characterization of biodegradable porous magnesium-based scaffolds containing silver for bone tissue engineering

Abstract Infection is a major potential complication in the clinical treatment of bone injuries. Magnesium (Mg)-based composites are biodegradable and antibacterial biomaterials that have been employed to reduce infection following surgical implants. The aim of present study was to synthesize and in-vitro characterize Mg-based scaffolds containing silver for bone tissue engineering. Porous Mg-based scaffolds with four silver concentrations (i.e., 0, 0.5 wt.%, 1 wt.%, and 2 wt.%), denoted by Mg–Ca–Mn–Zn–xAg (MCMZ–xAg) (where x is the silver concentration), were fabricated by the space holder technique. The effects of silver concentration on pore architecture, mechanical properties, bioactivity, and zone of bacterial inhibition were investigated in-vitro. X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and fluorescence microscopy were utilized to characterize the obtained scaffolds. In-vitro corrosion test results indicated that the MCMZ scaffolds with lower silver content were more resistant to corrosion than those enriched with higher amounts of silver. Examination of the antibacterial activity showed that the MCMZ–Ag scaffolds exhibited superb potential with respect to suppressing the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), in the inhibition zone around the MCMZ–Ag scaffolds, with increasing in the amount of incorporated silver; however, higher amounts of silver increased the cytotoxicity. Taken together, the results of this study demonstrate that the porous 0.5 wt.% Ag-containing scaffolds with interconnected pores, adequate mechanical properties, antibacterial activity, and cell adhesion are promising with respect to the repair and substitution of damaged and diseased bones.

Synthesis and characterization of a novel open cellular Mg-based scaffold for tissue engineering application

Tissue engineering is a field which aims to regenerate damaged tissues by enhancing tissue growth through the porous architecture of the scaffolds which is desired to mimic the human cancellous bone. Mg-based scaffolds are gaining importance in the field of tissue engineering owing to its potential application as a biomaterial. However, fabrication of porous Mg remains a daunting task due to its highly reactive nature. In the present work, a novel Mg-based open cell porous structure with pore interconnectivity and significant strength is successfully fabricated using powder metallurgy approach and Ti-woven wire mesh as a space holding material. Pore morphology and percentage porosity can be easily altered by adjusting the Ti-wire diameter and shape of construct. SEM, EDX and µ-CT analysis were performed to assess the microstructural properties of the fabricated scaffold which revealed a uniform distribution of pores with porosity varying in range 50–60%. The measured values of ultimate compressive strength and elastic modulus using quasi static compression test were found to be 101 MPa and 2 GPa, respectively. Further to improve corrosion resistance of fabricated scaffold, alloying and coating were carried out. Preliminary degradation study as well as cytocompatibility studies using L929 cells was carried out to validate the potential of fabricated scaffold for bone healing/repair applications. Fabricated porous structures showed improved corrosion resistance as well as cell viability of more than 90%, suggesting it as a promising development for bone scaffolding applications in future.

The Development and Investigation of Biocompatibility Properties of Biodegradable Magnesium–Zinc Scaffold Electrodeposited with Hydroxyapatite

In the present work, a biodegradable porous Mg–3 wt % Zn scaffold was synthesized by a powder metallurgical method and then a nano hydroxyapatite (HAP) coating with the composition of Ca10(PO4)6(OH)2 on the scaffold was produced by pulse electrodeposition and alkali treatment processes to increase the biodegradability and biocompatibility of the scaffold. The results showed that the as-deposited coating consisted of HAP, CaHPO4 ⋅ 2H2O (DCPD) and Ca8H2(PO4)6 ⋅ 5H2O (OCP) with needle-like and plate-like morphologies; the post-treated coating was composed of a needle-like structure of nano HAP developed almost perpendicularly to the substrate. Electrochemical tests indicated that the corrosion current density reduced from 1.531 × 10–3 to 3.78 × 10–5 A cm–2 and the corrosion potential of the scaffold increased from–1.448 to–1.366 V. The results showed higher biocompatibility and cell viabilities for as-coated and post-treated scaffold extracts than that for an uncoated scaffold. Also, MG63 cells were found to adhere and proliferate on the surface of the as-coated and post-treated scaffolds, making it a promising choice for medical applications. This study showed that electrodeposition of a HAP coating is a useful approach to increase the corrosion resistance and biocompatibility of the porous Mg–Zn scaffold in simulated body fluid and to develop Mg-based scaffolds.

Microstructure, Mechanical Properties and Corrosion Behavior of Porous Mg-6 wt.% Zn Scaffolds for Bone Tissue Engineering

Porous Mg-based scaffolds have been extensively researched as biodegradable implants due to their attractive biological and excellent mechanical properties. In this study, porous Mg-6 wt.% Zn scaffolds were prepared by powder metallurgy using ammonium bicarbonate particles as space-holder particles. The effects of space-holder particle content on the microstructure, mechanical properties and corrosion resistance of the Mg-6 wt.% Zn scaffolds were studied. The mean porosity and pore size of the open-cellular scaffolds were within the range 6.7-52.2% and 32.3-384.2 µm, respectively. Slight oxidation was observed at the grain boundaries and on the pore walls. The Mg-6 wt.% Zn scaffolds were shown to possess mechanical properties comparable with those of natural bone and had variable in vitro degradation rates. Increased content of space-holder particles negatively affected the mechanical behavior and corrosion resistance of the Mg-6 wt.% Zn scaffolds, especially when higher than 20%. These results suggest that porous Mg-6 wt.% Zn scaffolds are promising materials for application in bone tissue engineering.

Precise fabrication of open porous Mg scaffolds using NaCl templates: Relationship between space holder particles, pore characteristics and mechanical behavior

Mg-based scaffolds have great potential of application for bone defect repair due to their biodegradability and the excellent osteoinductivity, yet currently the fabrication of Mg-based porous materials is still a challenge. In this study, a new fabrication method was proposed to produce porous Mg scaffolds, which could be achieved by three steps: (1) defectless NaCl open porous template with enhanced relative density was prepared with NaCl particles by hot press sintering (HPS) process; (2) green compact of Mg and the NaCl template was produced by infiltration casting; (3) open porous Mg scaffold was achieved after leaching out the template. By using spherical NaCl particles and irregular polyhedral NaCl particles, respectively, two different types of templates were prepared, and correspondingly Mg scaffolds with spherical and irregular pores were respectively fabricated. The irregular-pore scaffold (I-scaffold) exhibited higher yield strength, while the spherical-pore scaffold (S-scaffold) showed superior interconnectivity and more stable compressive deformability due to the uniform spatial structure.

Design of magnesium alloys with controllable degradation for biomedical implants: From bulk to surface.

Owing to their unique mechanical properties, biodegradability, biocompatibility, Mg based biomaterials are becoming the most promising substitutes for tissue regeneration for impaired bone, vascular and other tissues because these scaffolds can provide not only ideal space for the growth and differentiation of seeded cells but also enough strength before the formation of normal tissues. The most important is that these scaffolds can be fully degraded after tissue regeneration, which can satisfy the increasing demand for better biomedical devices and functional tissue engineering biomaterials in the world. However, the rapid degradation rate of these scaffolds restricts the wide application in clinic. This paper reviews recent progress on how to control the degrdation rate based on the relevant corrosion mechanisms through the design of porous structure, phase structure, grains, and amorphous structure as well as surface modification, which will be beneficial to the better understanding and functional design of Mg-based scaffolds for wide clinical applications in tissue reconstruction in near futures.

Bacterial inhibition potential of 3D rapid-prototyped magnesium-based porous composite scaffolds–an in vitro efficacy study

Bone infections are common in trauma-induced open fractures with bone defects. Therefore, developing anti-infection scaffolds for repairing bone defects is desirable. This study develoepd novel Mg-based porous composite scaffolds with a basal matrix composed of poly(lactic-co-glycolicacid) (PLGA) and tricalcium phosphate (TCP). A unique low-temperature rapid prototyping technology was used to fabricate the scaffolds, including PLGA/TCP (PT), PLGA/TCP/5%Mg (PT5M), PLGA/TCP/10%Mg (PT10M), and PLGA/TCP/15%Mg (PT15M). The bacterial adhesion and biofilm formation of Staphylococcus aureus were evaluated. The results indicated that the Mg-based scaffolds significantly inhibited bacterial adhesion and biofilm formation compared to PT, and the PT10M and PT15M exhibited significantly stronger anti-biofilm ability than PT5M. In vitro degratation tests revealed that the degradation of the Mg-based scaffolds caused an increase of pH, Mg2+ concentration and osmolality, and the increased pH may be one of the major contributing factors to the antibacterial function of the Mg-based scaffolds. Additionally, the PT15M exhibited an inhibitory effect on cell adhesion and proliferation of MC3T3-E1 cells. In conclusion, the PLGA/TCP/Mg scaffolds could inhibit bacterial adhesion and biofilm formation, and the PT10M scaffold was considered to be an effective composition with considerable antibacterial ability and good cytocompatibility.

Effective cell growth potential of Mg-based bioceramic scaffolds towards targeted dentin regeneration

New emerging approaches in tissue engineering include incorporation of metal ions involved in various metabolic processes, such as Cu, Zn, Si into bioceramic scaffolds for enhanced cell growth and differentiation of specific cell types. The aim of the present work was to investigate the attachment, morphology, growth and mineralized tissue formation potential of Dental Pulp Stem Cells (DPSCs) seeded into Mg-based glass-ceramic scaffolds with incorporated Zn and Cu ions. Bioceramic scaffolds containing Si 60%, Ca 30%, Mg 7.5% and either Zn or Cu 2.5%, sintered at different temperatures were synthesized by the foam replica technique and seeded with DPSCs for up to 21 days. Scanning Electron Microscopy with associated Energy Dispersive Spectroscopy (SEM-EDS) was used to evaluate their ability to support the DPSCs's attachment and proliferation, while the structure of the seeded scaffolds was investigated by X-Ray Diffraction Analysis (XRD). Zn-doped bioceramic scaffolds promoted the attachment and growth of human DPSCs, while identically fabricated scaffolds doped with Cu showed a cytotoxic behaviour, irrespective of the sintering temperature. A mineralized tissue with apatite-like structure was formed on both Cu-doped scaffolds and only on those Zn-doped scaffolds heat-treated at lower temperatures. Sol-gel derived Zn-doped scaffolds sintered at 890oC support DPSC growth and apatite-like tissue formation, which renders them as promising candidates towards dental tissue regeneration.