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The aim of this systematic review was to assess the current scientific evidence of the antimicrobial potential of strontium (Sr) when used to functionalize titanium (Ti) for oral applications. Out of an initial list of 1081 potentially relevant publications identified in three electronic databases (MEDLINE via PubMed, Scopus, and Cochrane) up to 1 February 2021, nine publications based on in vitro studies met the inclusion criteria. The antimicrobial potential of Sr was investigated on different types of functionalized Ti substrates, employing different application methods. Nine studies reported on the early, i.e., 6-24 h, and two studies on the late, i.e., 7-28 days, antimicrobial effect of Sr, primarily against Staphylococcus aureus (S. aureus) and/or Escherichia coli (E. coli). Sr-modified samples demonstrated relevant early antimicrobial potential against S. aureus in three studies; only one of which presented statistical significance values, while the other two presented only the percentage of antimicrobial rate and biofilm inhibition. A relevant late biofilm inhibition potential against S. aureus of 40% and 10%-after 7 and 14 days, respectively-was reported in one study. Combining Sr with other metal ions, i.e., silver (Ag), zinc (Zn), and fluorine (F), demonstrated a significant antimicrobial effect and biofilm inhibition against both S. aureus and E. coli. Sr ion release within the first 24 h was generally low, i.e., below 50 mu g/L and 0.6 ppm; however, sustained Sr ion release for up to 30 days, while maintaining up to 90% of its original content, was also demonstrated. Thus, in most studies included herein, Sr-functionalized Ti showed a limited immediate (i.e., 24 h) antimicrobial effect, likely due to a low Sr ion release; however, with an adequate Sr ion release, a relevant antimicrobial effect, as well as a biofilm inhibition potential against S. aureus-but not E. coli-was observed at both early and late timepoints. Future studies should assess the ant

The aim of this systematic review was to assess the current scientific evidence of the antimicrobial potential of strontium (Sr) when used to functionalize titanium (Ti) for oral applications. Out of an initial list of 1081 potentially relevant publications identified in three electronic databases (MEDLINE via PubMed, Scopus, and Cochrane) up to 1 February 2021, nine publications based on in vitro studies met the inclusion criteria. The antimicrobial potential of Sr was investigated on different types of functionalized Ti substrates, employing different application methods. Nine studies reported on the early, i.e., 6-24 h, and two studies on the late, i.e., 7-28 days, antimicrobial effect of Sr, primarily against Staphylococcus aureus (S. aureus) and/or Escherichia coli (E. coli). Sr-modified samples demonstrated relevant early antimicrobial potential against S. aureus in three studies; only one of which presented statistical significance values, while the other two presented only the percentage of antimicrobial rate and biofilm inhibition. A relevant late biofilm inhibition potential against S. aureus of 40% and 10%-after 7 and 14 days, respectively-was reported in one study. Combining Sr with other metal ions, i.e., silver (Ag), zinc (Zn), and fluorine (F), demonstrated a significant antimicrobial effect and biofilm inhibition against both S. aureus and E. coli. Sr ion release within the first 24 h was generally low, i.e., below 50 mu g/L and 0.6 ppm; however, sustained Sr ion release for up to 30 days, while maintaining up to 90% of its original content, was also demonstrated. Thus, in most studies included herein, Sr-functionalized Ti showed a limited immediate (i.e., 24 h) antimicrobial effect, likely due to a low Sr ion release; however, with an adequate Sr ion release, a relevant antimicrobial effect, as well as a biofilm inhibition potential against S. aureus-but not E. coli-was observed at both early and late timepoints. Future studies should assess the ant

Plasma processing, e.g., functionalisation and deposition of antibacterial coatings, is often used to enhance surface properties of biomaterials. Plasma is, however, a non-uniform active medium, and the result of processing depends on the nature of both the plasma and the substratum. Here we show that when an antibacterial coating (i.e., polyterpenol) is plasma polymerised onto four types of titanium substrata that differ in their micro- and nano-scale topography (but not the bulk chemistry), the distribution of functional groups, e.g., –OH and –C[dbnd]O, in the polymer across the surface differs sufficiently, and so does the antibacterial activity of the resulting material system. While the addition of a coating hinders biofilm formation by Staphylococcus aureus and Pseudomonas aeruginosa, the bactericidal effect is significantly stronger in polymers deposited onto surfaces possessing lower degrees of nanoscale roughness, e.g., substrata after mechanical and chemical polishing. The reduced antibacterial efficacy of polymers on substrata with greater surface roughness (e.g., on mechanically polished or lotus leaf-like surfaces) is attributed to a greater extent of thickness non-uniformity and heterogeneity in the functional group distribution across the surface. These findings suggest that the magnitude and distribution of topographical features of the substratum should be considered when designing plasma-enabled surface modification strategies.

Titanium surface modification is critical for dental implant success. Our aim was to determine surfaces influence on dental pulp stem cells (DPSCs) viability and differentiation. Implants were divided into sandblasted/acid-etched (control) and sandblasted/acid-etched coated with calcium and magnesium ions (CaMg), supplied as composite (test). Proliferation was evaluated by MTT, differentiation checking osteoblastic gene expression, PGE2 secretion and matrix formation, inflammation by Interleukin 6 (IL-6) detection. MTT and IL-6 do not modify on test. A PGE2 increase on test is recorded. BMP2 is higher on test at early experimental points, Osterix and RUNX2 augment later. Alizarin-red S reveals higher matrix production on test. These results suggest that test surface is more osteoinductive, representing a start point for in vivo studies aiming at the construction of more biocompatible dental implants, whose integration and clinical performance are improved and some undesired effects, such as implant stability loss and further surgical procedures, are reduced.

Titanium surface modification is critical for dental implant success. Our aim was to determine surfaces influence on dental pulp stem cells (DPSCs) viability and differentiation. Implants were divided into sandblasted/acid-etched (control) and sandblasted/acid-etched coated with calcium and magnesium ions (CaMg), supplied as composite (test). Proliferation was evaluated by MTT, differentiation checking osteoblastic gene expression, PGE2 secretion and matrix formation, inflammation by Interleukin 6 (IL-6) detection. MTT and IL-6 do not modify on test. A PGE2 increase on test is recorded. BMP2 is higher on test at early experimental points, Osterix and RUNX2 augment later. Alizarin-red S reveals higher matrix production on test. These results suggest that test surface is more osteoinductive, representing a start point for in vivo studies aiming at the construction of more biocompatible dental implants, whose integration and clinical performance are improved and some undesired effects, such as implant stability loss and further surgical procedures, are reduced.

To improve cardiovascular implant success, metal-based stents are designated to modulate endothelial cells adhesion and migration in order to prevent restenosis and late thrombosis diseases. Biomimetic coatings with extra-cellular matrix adhesive biomolecules onto stents surfaces are a strategy to recover a healthy endothelium. However, the appropriate bioactive sequences to selective promote growth of endothelium and the biomolecules surface immobilization strategy remains to be elucidated. In this study, biofunctionalization of cobalt chromium, CoCr, alloy surfaces with elastin-like recombinamers, ELR, genetically modified with an REDV sequence, was performed to enhance metal surfaces endothelialization. Moreover, physical adsorption and covalent bonding were used as biomolecules binding strategies onto CoCr alloy. Surfaces were activated with plasma and etched with sodium hydroxide previous to silanization with 3-chloropropyltriethoxysilane and functionalized with the ELR. CoCr alloy surfaces were successfully biofunctionalized and the use of an ELR with an REDV sequence, allows conferring bioactivity to the biomaterials surface, demonstrating a higher cell adhesion and spreading of HUVEC cells on the different CoCr surfaces. This effect is emphasized as increases the amount of immobilized biomolecules and directly related to the immobilization technique, covalent bonding, and the increase of surface charge electronegativity. Our strategy of REDV elastin-like recombinamers immobilization onto CoCr alloy surfaces via covalent bonding through organosilanes provides a bioactive surface that promotes endothelial cell adhesion and spreading. (C) 2015 Elsevier B.V. All rights reserved., Peer Reviewed, Postprint (author’s final draft)

With an increasingly active and aging population, a growing number of orthopedic procedures are performed annually. However, traditional orthopedic implants face many complications such as infection, implant loosening, and poor host tissue integration leading to implant failure. Metal implant materials such as titanium and its alloys are widely used in orthopedic applications mainly based on their excellent mechanical properties and biological inertness. Since human bone extracellular matrix is nanometer in dimension comprised of rich nanostructured hydroxyapatite particles and collagen nanofibers, it is highly desirable to design a biologically-inspired nanostructured coating which renders the biocompatible titanium surface into a biomimetic and bioactive interface, thus enhancing osteoblast adhesion and promoting osseointegration. For this purpose, a biomimetic nanostructured coating based on nanocrystalline hydroxyapatite and single wall carbon nanotubes was designed. Specifically, nano hydroxyapatites with good crystallinity and biomimetic dimensions were prepared via a wet chemistry method and hydrothermal treatment. Microcrystalline hydroxyapatite with larger grain sizes can be obtained without hydrothermal treatment. The carbon nanotubes with different diameter and length were synthesized via an arc plasma method in the presence or absence of a magnetic field. Transmission electron microscopy images illustrate the regular, rod-like nanocrystalline and biomimetic nanostructure of hydrothermally treated nano hydroxyapatite. In addition, the length of carbon nanotubes can be significantly increased under external magnetic fields when compared to nanotubes produced without a magnetic field. More importantly, the in vitro study demonstrated for the first time that osteoblast and mesenchymal stem cell adhesion and proliferation were greater on titanium with hydrothermally treated nanocrystalline hydroxyapatites/magnetically treated carbon nanotubes, which suggests

Estrogen (17beta-estradiol) is involved in the regulation of bone formation, and estrogen deficiency results in decreased bone density and bone mass, as well as a decrease in pull-out strengths of implants. In previous studies, implant surface roughness was shown to affect the morphology, proliferation and differentiation of MG63 osteoblast-like cells, by inducing a more mature phenotype and by increasing production of local factors. The purpose of the current study was to investigate whether primary cultures of normal human female osteoblast (NHOst) cells respond in a similar fashion to these same surfaces and how these surfaces modulate cell response to 17beta-estradiol. Much of the Branemark literature supports the use of machined titanium surfaces for cases of suitable bone quality. Patients who present with less than ideal bone quality (i.e. osteoporotic bone) present a unique challenge to clinicians to enhance osseointegration that will allow masticatory function for many years to come. The possible effects of estrogen or estrogen deficiency on osseointegration are unclear. The in vitro model described here was designed to elucidate what effect, if any, did estrogen have on osteoblast response to titanium surface roughness, and conversely, what effect surface microtopography had on osteoblasts response to estrogen., The original document contains color images.