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Bactericidal ZnO@ZnS nanorod-array facilitates the attachment and migration of human gingival fibroblasts via properly controlling the release of zinc. • A ZnO@ZnS nanorod array was designed and successfully coated on pure titanium. • The Zn release by ZnO@ZnS nanorod array was gentler than that by the ZnO one. • The ZnO@ZnS nanorods were bactericidal while promoting the function of fibroblasts. Cell-selective toxic titanium is highly desired in clinical dental practice. Herein, based on the in situ conversion of ZnO to ZnO@ZnS, nanorod-array structured coatings with a controllable release features of zinc (Zn), has been successfully fabricated by a two-step hydrothermal method to endow titanium surface with cell-selectivity, i.e. boosting the functions (attachment and migration) of human gingival fibroblasts (HGnFs) while acting against the invasion of pathogenic bacteria. The improved functions of HGnFs over the ZnO@ZnS nanorod-array were attributed to the material's optimized zinc release, which was decreased from an order of 3.5 mg L−1 to about 0.3 mg L−1 (within the first week). But more importantly, this concentration still had a high antibacterial efficacy up to 100% (against both the S. aureus and E. coli , 107 CFU mL−1). This study demonstrated that a ZnO@ZnS nanorod-array coating could be a promising strategy to endow titanium dental implants with improved soft tissue sealing and effectively reduce peri-implantitis. [ABSTRACT FROM AUTHOR]

Prevention of periprosthetic infection (PPI) by inhibiting biofilm formation on prostheses is crucial to orthopedic surgery. In this work, silver nanoparticles (Ag NPs) are fabricated in situ and immobilized on titanium by silver plasma immersion ion implantation (PIII). The anti-biofilm activity rendered by the immobilized Ag NPs is assessed using Staphylococcus epidermidis , a biofilm producing strain, in vitro and in vivo . The immobilized Ag NPs show no apparent cytotoxicity but reduce biofilm formation in vitro by inhibiting bacteria adhesion and icaAD transcription. The immobilized Ag NPs offer a good defense against multiple cycles of bacteria attack in vitro , and the mechanism is independent of silver release. Radiographic assessment, microbiological cultures, and histopathological results demonstrate the ability of the functionalized surface against bacterial infection to reduce the risk of implant-associated PPI. [ABSTRACT FROM AUTHOR]

Surface modification of titanium based materials with balanced biological property, i.e. inhibit the adhesion of pathogenic bacteria but promote the positive functions of mammalian cells, is highly desired. Accordingly, titanium was successively treated with magnesium and silver plasma immersion ion implantation & deposition (Mg–Ag PIII&D). Scanning electron microscopy (SEM) observations revealed that nanoparticles were precipitated and bound to the titanium surface after Mg–Ag PIII&D. X-ray photoelectron spectroscopy (XPS) results indicated that these particles are metallic silver. Responses of both bacterial and mammalian cells were studied with Escherichia coli ( E. coli ) and osteoblast-like cell line MG63. The results indicated that the Mg–Ag PIII&D treated titanium inhibits the adhesion and proliferation of E. coli , but promotes the initial adhesion and alkaline phosphatase (ALP) expression of MG63 cells. It can be concluded that the antibacterial and osteogenic activities of titanium can be balanced by simultaneously taking advantage of the biological nature of magnesium and silver. [ABSTRACT FROM AUTHOR]

Highlights: [•] Zn was implanted into titanium using plasma immersion ion implantation technology. [•] The Zn-implanted titanium surfaces exhibited excellent osteogenic activity. [•] The Zn-implanted titanium surfaces possessed partly antibacterial effect. [Copyright &y& Elsevier]

Abstract: Titanium embedded with silver nanoparticles (Ag NPs) using a single step silver plasma immersion ion implantation (Ag-PIII) demonstrate micro-galvanic effects that give rise to both controlled antibacterial activity and excellent compatibility with osteoblasts. Scanning electron microscopy (SEM) shows that nanoparticles with average sizes of about 5 nm and 8 nm are formed homogeneously on the titanium surface after undergoing Ag-PIII for 0.5 h and 1 h, respectively. Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) indicate that those nanoparticles are metallic silver produced on and underneath the titanium surface via a local nucleation process from the solid solution of α-Ti(Ag). The Ag-PIII samples inhibit the growth of both Staphylococcus aureus and Escherichia coli while enhancing proliferation of the osteoblast-like cell line MG63. Electrochemical polarization and Zeta potential measurements demonstrate that the low surface toxicity and good cytocompatibility are related to the micro-galvanic effect between the Ag NPs and titanium matrix. Our results show that the physico-chemical properties of the Ag NPs are important in the control of the cytotoxicity and this study opens a new window for the design of nanostructured surfaces on which the biological actions of the Ag NPs can be accurately tailored. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fibrinogen assembly behaviors were first imaged by scanning electrochemical microscopy. • Fibrinogen assembly structures were only detectable in calcium-doped titanium surfaces. • A dye-assisted scanning electron microscopy method was developed to image fibrinogen assembly morphologies. Fibrinogen adsorption is a critical host response to the insertions of various medical devices. Scanning electrochemical microscopy (SECM) has the power to probe the local interactions between proteins and bulk solids in liquid environments; however, our knowledge of the distribution or the assembly structures of protein adsorption is limited. Here, fibrinogen assembly behaviors on calcium-doped titanium are imaged by resolving the strength of the SECM probe's negative feedback in two-dimensional micro-regions. By using ion implantation techniques, calcium and/or silver were doped into polished titanium surfaces. The calcium-doped titanium was capable of releasing calcium, while the clean titanium and silver-doped titanium did not release their constituents. The two-dimensional discontinuous distribution of the probe current/steady current ( i / i 0 ) values were only detectable in calcium-doped groups, and this was incubating duration dependent, showing the micro-regions preferential for fibrinogen assembly in calcium-doped groups. This was consistent with the fibrinogen adsorption morphologies on calcium-doped titanium examined by dye-assisted scanning electron microscopy. It is concluded that protein assembly behaviors on bulk solid surfaces in liquid environments can be imaged by resolving the distribution of the SECM probe currents in two-dimensional areas. The method is promising in illuminating the true surface-protein interactions and the protein adsorption structure–function relations. [ABSTRACT FROM AUTHOR]

Editor's Note: this Article has been retracted; the Retraction Note is available at https://doi.org/10.1038/s41598-021-88664-z. [ABSTRACT FROM AUTHOR]

Titanium (Ti) has been widely used as orthopedic and dental implants, it is very important to improve the osteogenic activity and antibacterial ability of titanium implants. The objective of this work was to investigate the osteogenic and antibacterial ability of the zinc (Zn) ion implanted Ti at different implantation voltage. X-ray photoelectron spectroscopy results indicate that Zn was successfully implanted into titanium. Zn-implanted titanium surfaces exhibit enhanced cell proliferation ability, alkaline phosphatase (ALP) activity, and partial resistance to both Escherichia coli ( E . coli ) and Staphylococcus aureus ( S . aureus ). The excellent osteogenic and antibacterial ability are highly related to the implantation voltage. The cell proliferation and antibacterial ability can be enhanced by increasing the implantation voltage from 15 kV to 30 kV, indicating that Zn implantation at 30 kV is more beneficial to both osteogenic and antibacterial ability. [ABSTRACT FROM AUTHOR]

Titanium implants possessing simultaneous osseointegration and antibacterial ability are desirable. In this work, three types of Zn/Ag micro-galvanic couples are fabricated on titanium by plasma immersion ion implantation to investigate the osseointegration and antibacterial effects as well as the involved mechanisms. The in vitro findings disclose enhanced proliferation, osteogenic differentiation, and gene expressions of the rat bone mesenchymal stem cells (rBMSCs), as well as good antibacterial ability on all three micro-galvanic couples. Excellent antimicrobial ability is also observed in vivo and the micro-CT and histological results reveal notable osseointegration in vivo despite the presence of bacteria. The Zn/Ag micro-galvanic couple formed on Zn/Ag dual-ion co-implanted titanium shows the best osseointegration as well as good antibacterial properties in vivo obtained from a rabbit tibia model. The difference among the three Zn/Ag micro-galvanic couples can be ascribed to the contact between the Ag NPs and Zn film, which affects the corrosion process. Our results indicate that the biological behavior can be controlled by the corrosion process of the Zn/Ag micro-galvanic couples. [ABSTRACT FROM AUTHOR]

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. [Copyright &y& Elsevier]

Background/Aims: Accumulating evidence demonstrates the superior osteoinductivity of tantalum (Ta) to that of titanium (Ti); however, the mechanisms underlying these differences are unclear. Thus, the objective of the present study was to examine the effects of Ta and Ti surfaces on osteogenesis using rat bone mesenchymal stromal cells (rBMSCs) as a model. Methods: Ta and Ti substrates were polished to a mirror finish to minimize the influences of structural factors, and the intrinsic surface effects of the two materials on the integrin α5β1/mitogen-activated protein kinases 3 and 1 (ERK1/2) cascade-mediated osteogenesis of rBMSCs were evaluated. Alkaline phosphatase (ALP) activity, Alizarin Red staining, real-time polymerase chain reaction, and western blot assays of critical osteogenic markers were conducted to evaluate the effects of the two substrates on cell osteogenesis. Moreover, the role of the integrin α5β1/ERK1/2 pathway on the osteoinductive performance of Ta and Ti was assessed by up- and down-regulation of integrin α5 and β1 with RNA interference, as well as through ERK1/2 inhibition with U0126. Results: Osteogenesis of rBMSCs seeded on the Ta surface was superior to that of cells seeded on the Ti surface in terms of ALP activity, extracellular matrix calcification, and the expression of integrin α5, integrin β1, ERK1/2, Runt-related transcription factor 2, osteocalcin, collagen type I, and ALP at both the mRNA and protein levels. Moreover, down-regulation of integrin α5 or integrin β1, or ERK1/2 inhibition severely impaired the osteoblastic differentiation on the Ta surface. By contrast, over-expression of integrin α5 or integrin β1 improved osteogenesis on the Ti substrates, while subsequent ERK1/2 inhibition abrogated this effect. Conclusion: The integrin α5β1/ERK1/2 pathway plays a crucial role in regulating rBMSCs osteogenic differentiation; thus, the greater ability of a Ta surface to trigger integrin α5β1/ERK1/2 signaling may explain its better osteoinductivity. The different effects of Ta and Ti surfaces on rBMSC osteogenesis are considered to be related to the conductive behaviors between integrin α5β1 and the oxides spontaneously formed on the two metals. These results should facilitate the development of engineering strategies with Ta and Ti surfaces for improved osteogenesis in endosteal implants. [ABSTRACT FROM AUTHOR]