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In order to improve the osseointegration and long-term survival of dental implants, it is urgent to develop a multifunctional titanium surface which would simultaneously have ...osteogeneic, angiogeneic and antibacterial properties. In this study, a potential dental implant material-dual Zn/Mg ion co-implanted titanium (Zn/Mg-PIII) was developed via plasma immersion ion implantation (PIII). The Zn/Mg-PIII surfaces were found to promote initial adhesion and spreading of rat bone marrow mesenchymal stem cells (rBMSCs) via the upregulation of the gene expression of integrin α1 and integrin β1. More importantly, it was revealed that Zn/Mg-PIII could increase Zn2+ and Mg2+ concentrations in rBMSCs by promoting the influx of Zn2+ and Mg2+ and inhibiting the outflow of Zn2+, and then could enhance the transcription of Runx2 and the expression of ALP and OCN. Meanwhile, Mg2+ ions from Zn/Mg-PIII increased Mg2+ influx by upregulating the expression of MagT1 transporter in human umbilical vein endothelial cells (HUVECs), and then stimulated the transcription of VEGF and KDR via activation of hypoxia inducing factor (HIF)-1α, thus inducing angiogenesis. In addition to this, it was discovered that zinc in Zn/Mg-PIII had certain inhibitory effects on oral anaerobic bacteria (Pg, Fn and Sm). Finally, the Zn/Mg-PIII implants were implanted in rabbit femurs for 4 and 12weeks with Zn-PIII, Mg-PIII and pure titanium as controls. Micro-CT evaluation, sequential fluorescent labeling, histological analysis and push-out test consistently demonstrated that Zn/Mg-PIII implants exhibit superior capacities for enhancing bone formation, angiogenesis and osseointegration, while consequently increasing the bonding strength at bone-implant interfaces. All these results suggest that due to the multiple functions co-produced by zinc and magnesium, rapid osseointegration and sustained biomechanical stability are enhanced by the novel Zn/Mg-PIII implants, which have the potential application in dental implantation in the future.
In order to enhance the rapid osseointegration and long-term survival of dental implants, various works on titanium surface modification have been carried out. However, only improving osteogenic activity of implants is not enough, because angiogenesis and bacteria inhibition are also very important for dental implants. In the present study, a novel dental implant material-dual Zn/Mg ion co-implanted titanium (Zn/Mg-PIII) was developed, which was found to have superior osteoinductivity, pro-angiogenic effects and inhibitory effects against oral anaerobes. Furthermore, synergistic effects of Zn/Mg ions on osteogenic differentiation of rBMSCs and the possible mechanism were discovered. In addition, rapid osseointegration and sustained biomechanical stability are greatly enhanced by Zn/Mg-PIII implants, which may have the potential application in dental implantation in the future. We believe this paper may be of particular interest to the readers.
Despite the widespread observations on the osteogenic effects of magnesium ion (Mg
), the diverse roles of Mg
during bone healing have not been systematically dissected. Here, we reveal a previously ...unknown, biphasic mode of action of Mg
in bone repair. During the early inflammation phase, Mg
contributes to an upregulated expression of transient receptor potential cation channel member 7 (TRPM7), and a TRPM7-dependent influx of Mg
in the monocyte-macrophage lineage, resulting in the cleavage and nuclear accumulation of TRPM7-cleaved kinase fragments (M7CKs). This then triggers the phosphorylation of Histone H3 at serine 10, in a TRPM7-dependent manner at the promoters of inflammatory cytokines, leading to the formation of a pro-osteogenic immune microenvironment. In the later remodeling phase, however, the continued exposure of Mg
not only lead to the over-activation of NF-κB signaling in macrophages and increased number of osteoclastic-like cells but also decelerates bone maturation through the suppression of hydroxyapatite precipitation. Thus, the negative effects of Mg
on osteogenesis can override the initial pro-osteogenic benefits of Mg
. Taken together, this study establishes a paradigm shift in the understanding of the diverse and multifaceted roles of Mg
in bone healing.
Copper has already been widely used in the modification of biomaterials because it possesses multifunctional biological effects like osteogenic, angiogenic and antibacterial activities. However, it ...is still not clear how different cell lines and bacteria will respond to different concentrations of Cu2+, which is very critical to the application of copper-doped implants.
This study aimed to explore the dose-response relationships of Cu2+ and its biological effects in vitro. Rat bone marrow mesenchymal stem cell (rBMSCs), mouse osteoblastic cell line (MC3T3-E1), and human umbilical vein endothelial cells (HUVECs) were used to evaluate cellular behaviors. Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were used to evaluate bacterial behaviors.
Results showed that the HUVECs exhibited significantly higher tolerance to copper ions than MC3T3-E1 and rBMSCs. The IC50 values of copper for HUVECs, MC3T3-E1 and HUVECs were approximated to 327.9 μM, 134.6 μM, and 0.7 μM, respectively. Besides, the threshold concentration of copper for effective inhibition against bacteria growth is 37 μM. When the concentration exceeded the threshold value, antibacterial activity could increase dramatically.
These results altogether establish a technological foundation for the application of copper-doped biomaterials in bone growth and remodeling.
Magnesium (Mg) is a vital engineering material owing to its light weight and excellent mechanical properties. However, poor corrosion resistance limits its widely applications as well as its economic ...value. Hence, surface modification is essential for Mg and its alloys. Among the various coatings, superhydrophobic coating, which is inspired by nature, has received increasing attentions in the past decade. With a water contact angle larger than 150°, superhydrophobic coating can provide sufficient protection for Mg-based substrates. The model of superhydrophobic states and the protection mechanism of superhydrophobic coating are discussed in this review. Especially, the methods for fabricating superhydrophobic coatings on Mg alloys are reviewed. Meanwhile, some functional superhydrophobic coatings on Mg alloys are summarized. Finally, the challenges and future directions are proposed. We hope that this paper will provide a serviceable review for future research on superhydrophobic coatings on Mg alloys.
Abstract Zinc (Zn) and silver (Ag) are co-implanted into titanium by plasma immersion ion implantation. A Zn containing film with Ag nanoparticles (Ag NPs) possessing a wide size distribution is ...formed on the surface and the corrosion resistance is improved due to the micro-galvanic couples formed by the implanted Zn and Ag. Not only are the initial adhesion, spreading, proliferation and osteogenic differentiation of rBMSCs observed from the Zn/Ag implanted Ti in vitro , but also bacteria killing is achieved both in vitro and in vivo . Electrochemical polarization and ion release measurements suggest that the excellent osteogenic activity and antibacterial ability of the Zn/Ag co-implanted titanium are related to the synergistic effect resulting from the long-range interactions of the released Zn ions and short-range interactions of the embedded Ag NPs. The Zn/Ag co-implanted titanium offers both excellent osteogenic activity and antibacterial ability and has large potential in orthopedic and dental implants.
After biomaterials are implanted into the human body, there are inevitable interactions between the biological environment and implant surfaces. Therefore, the surface of biomaterials has become one ...of the hottest research topics. Nanotechnology is a powerful tool in modern materials science and able to incorporate biomimicry on the nanoscale into materials engineering. Therefore, research on nanotechnology/nanostructured biomaterials has attracted much attention. A nano-functionalized surface has promising biological properties and clinical applications of biomaterials can be improved by producing a nanostructured surface. Many surface modification techniques have been adopted to produce nano-functionalized biomaterials surface, and in this paper, the fabrication, characterization, and properties of biomaterials such as ceramics, metals, and polymers with nanostructured surfaces are reviewed.
Background
Dental implant failures still occur because of peri‐implant diseases such as peri‐implantitis. The objective of this study was to treat peri‐implantitis in beagle dogs by fabricating ...minocycline hydrochloride (MH)‐loaded graphene oxide (GO) films on implant abutment surfaces.
Methods
Beagle dogs with silk ligature were used to establish the peri‐implantitis model. Modified sulcus bleeding index, peri‐implant probing pocket depth, radiographic evaluation, micro‐CT tomography analysis, and histological evaluation were determined to evaluate the therapeutic effect of MH‐loaded GO films on abutment surfaces for peri‐implantitis.
Results
Radiographic and micro‐CT analysis showed that lots of marginal bone loss could be found on Ti and MH/Ti groups, especially for Ti group. Little bone less could be seen on GO/Ti group while bone less on MH/GO/Ti group was negligible. Results of the histological analysis presented that lots of neutrophils could be found on Ti and MH/Ti groups. However, almost none of the neutrophils could be observed on GO/Ti and MH/GO/Ti while lots of osteocytes could be found.
Conclusion
MH‐loaded GO films on implant abutment surfaces could prevent the further development of peri‐implantitis and exhibit good therapeutic effect for peri‐implantitis in beagle dogs.
In recent years, magnesium (Mg) alloys show a promising application in clinic as degradable biomaterials. Nevertheless, the poor corrosion resistance of Mg alloys is the main obstacle to their ...clinical application. Here we successfully seal the pores of plasma electrolytic oxidation (PEO) coating on AZ31 with Mg-Al layered double hydroxide (LDH) via hydrothermal treatment. PEO/LDH composite coating possess a two layer structure, an inner layer made up of PEO coating (~5 μm) and an outer layer of Mg-Al LDH (~2 μm). Electrochemical and hydrogen evolution tests suggest preferable corrosion resistance of the PEO/LDH coating. Cytotoxicity, cell adhesion, live/dead staining and proliferation data of rat bone marrow stem cells (rBMSCs) demonstrate that PEO/LDH coating remarkably enhance the cytocompatibility of the substrate, indicating a potential application in orthopedic surgeries. In addition, hemolysis rate (HR) test shows that the HR value of PEO/LDH coating is 1.10 ± 0.47%, fulfilling the request of clinical application. More importantly, the structure of Mg-Al LDH on the top of PEO coating shows excellent drug delivery ability.
Titanium (Ti) and its alloys are widely used as orthopedic and dental implants. In this work, zinc (Zn) was implanted into oxalic acid etched titanium using plasma immersion ion implantation ...technology. Scanning electron microscopy and X-ray photoelectron spectroscopy were used to investigate the surface morphology and composition of Zn-implanted titanium. The results indicate that the depth profile of zinc in Zn-implanted titanium resembles a Gaussian distribution, and zinc exists in the form of ZnO at the surface whereas in the form of metallic Zn in the interior. The Zn-implanted titanium can significantly stimulate proliferation of osteoblastic MC3T3-E1 cells as well as initial adhesion, spreading activity, ALP activity, collagen secretion and extracellular matrix mineralization of the rat mesenchymal stem cells. The Zn-implanted titanium presents partly antibacterial effect on both Escherichia coli and Staphylococcus aureus. The ability of the Zn-implanted titanium to stimulate cell adhesion, proliferation and differentiation as well as the antibacterial effect on E. coli can be improved by increasing implantation time even to 2 h in this work, indicating that the content of zinc implanted in titanium can easily be controlled within the safe concentration using plasma immersion ion implantation technology. The Zn-implanted titanium with excellent osteogenic activity and partly antibacterial effect can serve as useful candidates for orthopedic and dental implants.
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•The 3D porous sulfonated polyetheretherhetone (PEEK) was proposed for the application in drug delivery.•Controllable and durable BMP-2 release could be successfully achieved.•The ...osteogenic differentiation activity of BMP-2-loaded PEEK materials was optimized.
Polyetheretherketone (PEEK) is ideal for dental and orthopedic applications because its mechanical properties are similar to cortical bones. However, its inherent inert ability hinders its clinical applications. In this work, bone morphogenetic protein-2 (BMP-2) was immobilized onto the sulfonated PEEK (SPEEK) using lyophilization technology. The surface morphologies of the samples were analyzed by field-emission scanning electron microscopy (FE-SEM), and the chemical compositions were analyzed by energy-dispersive X-ray spectrometry (EDS). The release content of BMP-2 of the samples immersed in the PBS (pH = 7.4) was detected by a human BMP-2 ELISA kit. The results indicated that controllable and durable BMP-2 release was accomplished due to the three-dimensional (3D) network of sulfonated PEEK. The in vitro cellular experiments showed that the BMP-2-immobilized samples significantly enhanced the initial adhesion and spreading of rat bone mesenchymal stem cells (rBMSCs). Moreover, the collagen secretion, extracellular matrix mineralization and ALP activity were also improved. Thus, the BMP-2-immobilized samples greatly promoted the osteogenic differentiation of rBMSCs, which revealed that BMP-2 immobilization paves the way for the use of PEEK in clinical applications.
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