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The idea of permanent tooth replacement goes back to the year 2000 BC at least, when carved bamboo pegs were used to replace missing teeth in ancient China. The phenomenon of osseointegration, however, was not verified until the mid-1960s, when Branemark discovered that titanium could integrate to bone. Since then, the osseointegration capacity of implants has been profoundly investigated and implants as such have evolved enormously in all possible aspects, from material selection and processing to specific surface engineering, among many others. This review article, in particular, focuses on dental implants and aims to introduce the main concerns involved in modern dentistry, concentrating especially on the importance of finding an effective way to prevent peri-implantitis. In this sense, strategies such as shifting from metal to ceramic implant components and applying novel antimicrobial antibiotic-free coatings seem to be taking the lead., This article has been supported by MIS Foundation for basic and applied research on peri-implantitis

In this work ternary bioactive glasses with the molar composition 63 % SiO2, 28 % CaO, and 9 % P2O5 have been prepared via sol-gel processing route leading to xerogel or aerogel glasses, depending on the drying conditions. Two types of drying methods were used: atmospheric pressure drying (evaporative), to produce xerogels, and supercritical fluids drying, to obtain aerogels. Both dried gels were subjected to heat-treatment at three different temperatures: 400, 600 and 800 ºC in order to the removal of synthesis byproducts and structural modifications. The resulting materials were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and differential thermal analysis (DTA), and by in vitro bioactivity tests in simulated body fluid. The influence of the drying and the sintering temperature of their structure, morphology, and bioactivity of the final products were evaluated. The results show a good bioactivity of xerogel and aerogel bioactive glass powders with the formation of an apatite layer after one day of immersion in SBF solution for aerogel bioactive glass powders and a particle size less than 10 nm. An apatite layer formed after 3 days in the case of xerogel bioactive glass powders and a particle size around 100 nm.

This work is a study of the properties of TiO2-anatase nanoparticles attached by a low-melting point inorganic glass (530°C). Unlike other low-melting glasses, this composition does not contain any toxic metal. Likewise, it shows an excellent wettability on ceramic nanoparticles. A small addition of 5 vol% of glass remarkably enhances the mechanical strength of the composites with respect to pure TiO2 calcined at the same temperature, becoming twice this value. Self-cleaning properties analyzed using the methylene blue 385 nm UV-A photodegradation test showed that, after different UV-light periods, the photo-efficiency of TiO2-anatase was not altered by the presence of this glass., This work was supported by CSIC under grant 201960E103 and by the Spanish Ministry of Science Innovation and Universities (MCIU/AEI/FEDER, UE) under award RTI2018-094958-B-I00. Dr. Borrell acknowledges the Spanish Ministry of Economy and Competitiveness for her RyC contract (RYC-2016-20915).

In this research, low-melting phosphate (LMP) glasses (G1, G2, G3) were employed as green flame-retardant synergist additives in epoxy (EP)/ammonium polyphosphate (APP) composite. To investigate their performance as flame-retardant additives, comprehensive fire tests and characterizations were carried out, including limiting oxygen index test, UL-94 vertical burning test, cone calorimeter test, real-time temperature detection, X-ray microtomography, and char residue strength analysis. A prominent improvement of flame-retardant properties was observed in EP composites containing LMP glasses. EP/9%APP/1%G1 reached V-0 rating in UL-94 test and showed a decreased peak heat release rate by around 40% over EP/10%APP in the cone calorimeter test. It found that LMP glasses mainly showed the physical barrier effect in the condensed phase flame retardancy. Interestingly, via simulating different combustion temperatures, LMP glasses reveal different flame-retardant performance. The mechanism was further elucidated as: A match between the LMP glass phase-transition temperature range and the combustion temperature contributed to the optimized flame-retardant performances. This result provided enlightenment for the design and application of phase-transition additives toward improving the flame-retardant properties in polymer composites., Mr. Wei Liu is supported by China Scholarship Council (CSC) (File No. 201504910748).

A modified 45S5 Bioglass® containing 2 mol% alumina and 2 mol% strontium oxide was prepared. In vitro bioactivity in powder and monolithic samples was conducted. Fourier transform infrared analysis and pH change in simulated body fluid were investigated for powder samples after 480 min of immersion. Additionally, X-ray diffraction and scanning electron microscopy after 7 and 14 days of immersion in simulated body fluid were investigated for monolithic samples. The formation of phosphate and carbonate phase precursors of hydroxycarbonate apatite was observed after 480 min for powder samples, and the hydroxycarbonate apatite pattern and morphology were confirmed after 7 days of immersion for monolithic samples. It seems that changes in composition did not affect reactivity but caused a decrease in the maxima of pH. Cytotoxicity and cell viability obtained by using the NCTC clone 929 cell line did not show any significant loss of cell viability or cytotoxicity. Moreover, after overnight incubation, the samples demonstrated safe disinfection for Escherichia coli. For these reasons, the use of these new bioactive glasses can be considered a promising alternative for the reconstruction of bone defects and even for the treatment and suppression of bone infections., This research was performed with support from the Brazilian government through the funding agencies CAPES (CsF/PDSE-Project No 88881.189953/2018–01), CNPq (GD-Project No 142172/2016–2, Universal Research Project No 481260/2012–9 and PD. 312135/2016–5) and FAPESP (Project No 1999/01924–2).

In this paper we have investigated and demonstrated the antimicrobial capabilities of nano-silver-4 wt%-kaolin (nAg-4-Kn) composite supported on borosilicate glass beads (BGB). Tests have been conducted in a fixed bed reactor on effluent from the secondary clarifier of a conventional wastewater treatment plant (WWTP) in Abu Dhabi, United Arab Emirates (UAE). The prepared BGB with immobilized nAg-4-Kn (nAg-4-Kn/BGB) were characterized using the RAMAN spectroscopy, TEM equipped with EDX and Focus Ion Beam Scanning Electron Microscope (FIB-SEM) techniques. The rate of disinfection was assessed through Luria-Bertani (LB)-agar plate cell counting technique. The results showed complete disinfection after few hours, which was preserved even after several days in repeated runs. The nAg-4-Kn/BGB was reused, demonstrating that the immobilization of nAg-4-Kn was stably achieved, and the activity and integrity of the composites on the BGB were preserved. First order disinfection kinetic constants were estimated to be 2.76 cm h−1 and 2.56 cm h−1 in two consecutive runs. Analyses of the beads after the experiments showed minor losses of nAg from the kaolin matrix thereby corroborating reusability of these materials.

This article belongs to the Special Issue Antimicrobial Material in Dentistry., Current endodontic procedures continue to be unsuccessful for completely removing pathogens present inside the root canal system, which can lead to recurrent infections. In this study, we aimed to assess the antimicrobial capacity and tissue response of two inorganic bactericidal additives incorporated into a paste root canal sealer on contaminated root dentin in vivo. An experimental study was performed in 30 teeth of five Beagle dogs. After inducing microbiological contamination, root canal systems were treated by randomly incorporating one of two antimicrobial additives into a commercial epoxy-amine resin sealer (AH Plus), i.e., G3T glass-ceramic (n = 10) and ZnO-enriched glass (n = 10); 10 samples were randomized as a control group. After having sacrificed the animals, microbiological, radiological, and histological analyses were performed, which were complemented with an in vitro bactericidal test and characterization by field emission scanning electron microscopy. The tested groups demonstrated a non-significant microbiological reduction in the postmortem periapical index values between the control group and the bactericidal glass-ceramic group (p = 0.885), and between the control group and the ZnO-enriched glass group (p = 0.169). The histological results showed low values of inflammatory infiltrate, and a healing pattern characterized by fibrosis in 44.4% of the G3T glass-ceramic and 60.0% of ZnO-enriched glass. Bactericidal glassy additives incorporated in this root canal sealer are safe and effective in bacterial reduction.

This study investigates a novel approach to controlling biofilms of the most frequent pathogens implicated in the etiology of biomaterials-associated infections. New bactericidal filler based on a non-toxic glass, belonging to B2O3-SiO2-Al2O3-Na2O-ZnO system, was used to formulate composites of the most widely used polymers in biomedical applications [i.e. thermoplastic polyurethane (TPU) and polydimethyl siloxane (PDMS)], with varying percentage by weight of the bactericidal glass (5, 15, 25, 35, 50%). Glass-filled polymer composites show dramatically restricted bacterial colonisation and biofilm formation. They exhibit time- and dose-dependent killing, with maximal action at 5 days. The highest activity was found against S.epidermidis biofilm (99% of reduction), one of the most common cause of nosocomial infections. The tensile properties of the obtained glass-filled composites are comparable with the literature data concerning polymeric biomaterials for medical implants and devices. In addition, all the materials presented in this research, revealed an excellent biocompatibility. This was disclosed by cell viability values above 70%, none alteration on erythrocyte membrane or cell functionality in contact with materials (haemolytic index 0–2%), and absence of interferences in blood coagulation (intrinsic, extrinsic and final pathways)., B. Cabal acknowledges financial support from Jovellanos program (IDEPA, cofounded by FEDER).

[Objectives] To compare biofilm formation on the surface of different ceramic biomaterials to be used in implant dentistry., [Methods] In vitro biofilm formation was investigated from mixtures of standard reference strains of Streptococcus oralis, Veillonella parvula, Actinomyces naeslundii, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. Sterile ceramic calcium hydroxyapatite discs (HA) as control, sterile Al2O3/Ce-TZP nanocomposite sandblasted discs (material A1) and sterile Al2O3/Ce-TZP nanocomposite sandblasted discs and coated with two types of antimicrobial glasses (materials A2 and A3) were used. Biofilms were grown on the four surfaces and evaluated after 12, 24, 48 and 72 h of incubation. Biofilms were examined by confocal laser scanning microscopy (CLSM). In addition, counts of live bacterial cells of the target species A. actinomycetemcomitans, F. nucleatum and P. gingivalis were calculated by quantitative polymerase chain reaction (qPCR) combined with propidium monoazide (PMA). For data analysis, bacterial counts were compared with a multivariate general lineal model., [Results] Using CLSM, cell vitality decreased in A2 and A3. With qPCR-PMA, significant differences in vitality were observed forA. actinomycetemcomitans in A3 after 48 and 72 h of incubation. With respect to the development of the biofilms, a significant increase in counts on HA and materials A1 and A2 was observed for A. actinomycetemcomitans and F. nucleatum. Conversely, for P. gingivalis, no differences were found for HA and materials A1 and A2., [Significance] Differences in biofilm formation were detected among the different tested materials. The ceramic material A3 has an effect on the vitality of A. actinomycetemcomitans growing in an in vitro biofilm model., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under the project MAT2012-38645. A.L.-P. and M.C.S. received funding from Extraordinary Chair of DENTAID-UCM.

This study details the relationship between the structure, chemical composition and thermal properties of a series of calcium sodium phosphate glasses belonging to xP2O5-yCaO-(100−x−y)Na2O system, which have been prepared by melt-quenching method. The glass compositions were limited by fixing the P2O5 content (x) to 40, 45, 50, 55 and 60 mol%, and varying the CaO mol% (y) at 10, 15, 20, 25, 30 mol%. Glass transition (Tg) and melting temperatures (Tm) show a clear relationship with composition. The polymerization of the glass structure increases the higher the content of P2O5 leading to an increase in Tg and Tm temperatures. Higher contents of calcium improve the phosphate network strength increasing Tg and Tm temperatures. Sodium ions, displaying lower charge-to-size ratio than calcium ions, decrease the phosphorous condensation reducing the Tg and Tm temperatures of glasses. The results obtained in this investigation show the feasibility to develop extremely low melting calcium sodium phosphate glasses with P2O5 content of 45 mol%. Those results laid the foundation of employing these calcium sodium phosphate glasses as amorphous low melting temperature materials for further applications involving: a) melting temperature adjustment, such as fire-retardant additive in polymer composites; b) nanoparticle binder, due to its low melting temperature, nanoparticles can be safely embedded into this glass avoiding thermal coalescence. Examples of such applications are described in this work., Wei Liu was supported by China Scholarship Council (CSC) (File No. 201504910748).

The aim of the study is to evaluate, in a ligature-induced periodontitis model, the efficacy of a commercially available dental resin containing different antimicrobial glass/glass-ceramic additions (0&ndash, 26 wt.%). It has been proved that a 26 wt.% glass addition to a conventional dental resin matrix does not alter neither its workability nor its adhesion to the surface of teeth, however, it does confer notable antimicrobial properties when tested in vitro. Moreover, in vivo tests in Beagle dogs demonstrated the prevention of bone loss in ligature-induced plaque accumulation around teeth. Particularly, the glass-ceramic filler resin composite has shown excellent antimicrobial control since it displays the same bone loss as that of the negative control. The results obtained in the present investigation have shown that a conventional dental resin containing a fraction of glass/glass-ceramic (&ge, 26 wt.%) can prevent periodontitis, which is considered to be a most serious dental disease.

Bacterial and fungal infections remain a major clinical challenge. Implant infections very often require complicated revision procedures that are troublesome to patients and costly to the healthcare system. Innovative approaches to tackle infections are urgently needed. We investigated the histological response of novel free P 2 O 5 glass-ceramic rods implanted in the jaws of beagle dogs. Due to the particular percolated morphology of this glass-ceramic, the dissolution of the rods in the animal body environment and the immature bone formation during the fourth months of implantation maintained the integrity of the glass-ceramic rod. No clinical signs of inflammation took place in any of the beagle dogs during the four months of implantation. This new glass-ceramic biomaterial with inherent bactericidal and fungicidal properties can be considered as an appealing candidate for bone tissue engineering., This work was supported by the Spanish Ministry of Science and Innovation (MICINN) under the projects MAT2012-38645. A.P. Tomsia work was supported by the National Institutes of Health/National Institute of Dental and Craniofacial Research (NIH/NIDCR) Grant No. 1R01DE015633.

This paper reports the fabrication, microstructural characterization, mechanical properties and antimicrobial activity of scaffolds obtained from a soda-lime glass powder constituted by micro-spheres belonging to the SiO-NaO-AlO-CaO - BO system. Scaffolds with a porosity > 90% were fabricated using the foam replication method in the temperature range of 750-850 °C. The highest compressive strength value (0.2 MPa) was obtained for the scaffolds sintered at 850 °C. The observed mechanical properties were rationalized considering the scaffold singular microstructure of the struts constituted by a dense packing of microspheres ranging from 4 to 30 μm interlocked by nepheline needle-like crystals. The antimicrobial test was performed against three different microorganisms: Escherichia coli, Staphylococcus aureus and Candida krusei (yeast). A 45S5 Bioglass® scaffold was also tested for comparison. A window glass scaffold was used as control. In all cases a safe disinfection was obtained (reduction > 99.9% = log of reduction > 3). The antimicrobial activity was found to be similar to that of 45S5 Bioglass® based scaffolds. However, the soda-lime scaffold sintered at 850 °C exhibited a higher antimicrobial activity (log of reduction > 5 = reduction > 99.999%) against C. krusei, which is a microorganism resistant to multiples biocides, than the Bioglass® scaffold (log of reduction < 2 = reduction > 99.0%)., This work was supported by the Spanish Ministry of Science and Innovation (MICINN) and CSIC under the Projects MAT2012-38645 and 201360E012 respectively. Thanks are due to the Spanish Society of Implantology (SEI) for their support. Kai Zheng acknowledges the scholarship from China Scholarship Council (CSC, NO. 201206740003).

Antimicrobial coatings based on a family of non-toxic, antimicrobial glass that belongs to the SiO-NaO-AlO-CaO-BO system, were thermally sprayed on titanium plates by high velocity suspension flame spraying (HVSFS). Atomized glass microspheres (, This study has been supported by the Spanish Ministry of Science and Innovation MAT2012-38645. C. Prado acknowledges financial support from JAE-Doc program (CSIC, cofounded by FSE). Also the authors would like to express their gratitude to the Ministry of Education and Science of the Russian Federation in the frame of Governmental Regulation of the Russian Federation n° 220, 9th of April 2010, by Contract 14.B25.31.0012, 26th of June 2013.

The prevention and treatment of post-surgical infections is an ongoing concern. Post-surgical infections often cannot be treated with commercially available antibiotic-loaded bone cement as because higher doses of antibiotics are required. We describe here an approach to prevent implant infection through the use of glass coatings combined with silver nanoparticles deposited by sedimentation and heat-treated at 980 °C on titanium alloys. Silver is nontoxic to the human tissue and has been used as an anti-infective for centuries. The glass/silver coatings are composed of a soda-lime glassy matrix containing silver nanoparticles ranging from 2.6 to 20. wt.%. Optimum firing conditions have been determined for the fabrication of coatings that adhere well to the metal implant. These final coatings do not crack or delaminate. The biocidal activity of these coatings was also investigated. Coatings containing 20. wt.% of silver nanoparticles exhibited excellent biocidal activity (log η> 5) against Gram+, Gram- bacteria, and yeast after 24 h. © 2012 Elsevier Ltd., This work has been supported by ITMA (Asturias, Spain) under contract number 20102141, Spanish MICINN, MAT2009-14542-C02-01 and by the National Institutes of Health (NIH/NIDCR) under grant number 5R01 DE015633.

et al., The biocide efficiency of bioactive 45S5 Bioglass ® derived glass-ceramic substrates against common Gram positive and Gram negative bacteria, and also against yeast, is investigated in this study. The results confirm the high bactericidal capacity of this material. Inorganic coatings containing silver nanoparticles on glass-ceramic substrates are developed in order to ascertain whether the presence of silver enhances the biocide activity. It is found that a coating made of soda-glass containing silver nanoparticles does not improve the antifungal properties of the 45S5 Bioglass ® derived glass-ceramic substrates. © 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.

The preparation of activated carbons from bean pods by chemical (K(2)CO(3)) and physical (water vapor) activation was investigated. The carbon prepared by chemical activation presented more developed porous structure than one obtained by water vapor activation. Carbon adsorbent with very low ash content and developed micropore structure is obtained by thermochemical treatment with conc.H(2)SO(4) of liquid products from carbonization of bean pods and activation with water vapour. Publisher's Version Q4 WOS:000207441900002

The hydrophobic-hydrophilic character of a series of microporous activated carbons was explored as a key factor in competitive adsorption of a non-polar compound from liquid phase. The selectivity of the carbon surface towards naphthalene was explored by performing the adsorption isotherms in water, cyclohexane and heptane. Solvent polarity and adsorbent hydrophobic character were found to strongly influence the adsorption capacity of naphthalene. In aqueous media, despite the non-polar character of the adsorbate, surface acidity lowered adsorption capacity. This is attributed to the competition of water from the adsorption sites, via H-bonding with surface functionalities and the formation of hydration clusters that reduce the accessibility and affinity of naphthalene to the inner pore structure. In organic media the uptake decreased due to competition of the hydrophobic solvent for the active sites of the carbon and to solvation effects. This competitive effect of the solvent is minimized in oxidized carbons as opposed to the trend obtained in aqueous solutions. The results confirmed that although adsorption of naphthalene strongly depends on the narrow microporosity of the adsorbent, competitive adsorption of the solvent for the active sites becomes important.

This is an open access article distributed under the terms of the Creative Commons Attribution License.-- et al., [Objectives]: The aim of the present study is to evaluate, in a ligature-induced peri-implantitis model, the efficacy of three antimicrobial glassy coatings in the prevention of biofilm formation, intrasulcular bacterial growth and the resulting peri-implant bone loss. [Methods]: Mandibular premolars were bilaterally extracted from five beagle dogs. Four dental implants were inserted on each hemiarch. Eight weeks after, one control zirconia abutment and three with different bactericidal coatings (G1n-Ag, ZnO35, G3) were connected. After a plaque control period, bacterial accumulation was allowed and biofilm formation on abutments was observed by Scanning Electron Microscopy (SEM). Peri-implantitis was induced by cotton ligatures. Microbial samples and peri-implant crestal bone levels of all implant sites were obtained before, during and after the breakdown period. [Results]: During experimental induce peri-implantitis: colony forming units counts from intrasulcular microbial samples at implants with G1n-Ag coated abutment remained close to the basal inoculum; G3 and ZnO35 coatings showed similar low counts; and anaerobic bacterias counts at control abutments exhibited a logarithmic increase by more than 2. Bone loss during passive breakdown period was no statistically significant. Additional bone loss occurred during ligature-induce breakdown: 0.71 (SD 0.48) at G3 coating, 0.57 (SD 0.36) at ZnO35 coating, 0.74 (SD 0.47) at G1n-Ag coating, and 1.29 (SD 0.45) at control abutments; and statistically significant differences (p, This work was supported by the Spanish Ministry of Science and Innovation (MICINN) and The Spanish National Research Council (CSIC) under the projects MAT2012-38645 and 201360E012 respectively. B. Cabal acknowledges financial support from JAE-Doc program (CSIC, cofounded by FSE).

This is an open-access article distributed under the terms of the Creative Commons Attribution License., The aim of the present study was to evaluate bone loss at implants connected to abutments coated with a soda-lime glass containing silver nanoparticles, subjected to experimental peri-implantitis. Also the aging and erosion of the coating in mouth was studied. Five beagle dogs were used in the experiments. Three implants were placed in each mandible quadrant: in 2 of them, Glass/n-Ag coated abutments were connected to implant platform, 1 was covered with a Ti-mechanized abutment. Experimental peri-implantitis was induced in all implants after the submarginal placement of cotton ligatures, and three months after animals were euthanatized. Thickness and morphology of coating was studied in abutment cross-sections by SEM. Histology and histo-morphometric studies were carried on in undecalfied ground slides. After the induced peri-implantitis: 1.The abutment coating shown losing of thickness and cracking. 2. The histometry showed a significant less bone loss in the implants with glass/n-Ag coated abutments. A more symmetric cone of bone resorption was observed in the coated group. There were no significant differences in the peri-implantitis histological characteristics between both groups of implants. Within the limits of this in-vivo study, it could be affirmed that abutments coated with biocide soda-lime-glass-silver nanoparticles can reduce bone loss in experimental peri-implantitis. This achievement makes this coating a suggestive material to control peri-implantitis development and progression. © 2014 Martinez et al., This work was supported by the Spanish Ministry of Science and Innovation (MICINN) under the projects MAT2009-14542-C02-01 and MAT2012-38645. B. Cabal thanks the CSIC JAE-Doc Program for a postdoctoral contract.

This is an open access article distributed under the Creative Commons Attribution License.-- This article belongs to the Special Issue "Biologic Coatings for Orthopaedic Implant"., The present work presents new bactericidal coatings, based on two families of non-toxic, antimicrobial glasses belonging to B2O3-SiO2-Na2O-ZnO and SiO2-Na2O-Al2O3-CaO-B2O3 systems. Free of cracking, single layer direct coatings on different biomedical metallic substrates (titanium alloy, Nb, Ta, and stainless steel) have been developed. Thermal expansion mismatch was adjusted by changing glass composition of the glass type, as well as the firing atmosphere (air or Ar) according to the biomedical metallic substrates. Formation of bubbles in some of the glassy coatings has been rationalized considering the reactions that take place at the different metal/coating interfaces. All the obtained coatings were proven to be strongly antibacterial versus Escherichia coli (>4 log). © 2014 by the authors; licensee MDPI, Basel, Switzerland., This study has been supported by CSIC project reference number 201360E012 and by the Spanish Ministry of Science and Innovation MAT2012-38645. C. Prado and B. Cabal acknowledge financial support from JAE-Doc program (CSIC, cofounded by FSE)., We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License., In the attempt to find valid alternatives to classic antibiotics and in view of current limitations in the efficacy of antimicrobial-coated or loaded biomaterials, this work is focused on the development of a new glass-ceramic with antibacterial performance together with safe biocompatibility. This bactericidal glass-ceramic composed of combeite and nepheline crystals in a residual glassy matrix has been obtained using an antimicrobial soda-lime glass as a precursor. Its inhibitory effects on bacterial growth and biofilm formation were proved against five biofilm-producing reference strains. The biocompatibility tests by using mesenchymal stem cells derived from human bone indicate an excellent biocompatibility., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under the projectMAT2012-38645, and by CSIC project ref. nu 201360E012. B. Cabal acknowledges financial support from JAE-Doc program (CSIC, cofounded by FSE).

Nanocomposites made of non-woven glass fibres with diameters ranging from tens of nanometers up to several micrometers, containing silver nanoparticles, were successfully fabricated by the laser spinning technique. Pellets of a soda-lime silicate glass containing silver nanoparticles with varying concentrations (5 and 10 wt%) were used as a precursor. The process followed to obtain the silver nanofibres did not agglomerate significantly the metallic nanoparticles, and the average particle size is still lower than 50 nm. This is the first time that glass nanofibres containing silver nanoparticles have been obtained following a process different from electrospinning of a sol–gel, thus avoiding the limitations of this method and opening a new route to composite nanomaterials. Antibacterial efficiency of the nanosilver glass fibres, tested against one of the most common Gram negative bacteria, was greater than 99.99% compared to the glass fibres free of silver. The silver nanoparticles are well-dispersed not only on the surface but are also embedded into the uniform nanofibres, which leads to a long lasting durable antimicrobial effect. All these novel characteristics will potentially open up a whole new range of applications., This work was supported by Xunta de Galicia (10DPI303014PR) and the Spanish Ministry of Science and Innovation (MICINN) under the project MAT2009-14542-C02-02.

A soda-lime glass with a strong biocide activity has been used to obtain titanium alloy and zircon oxide glass-ceramic coatings for dental applications. The mechanical stability, adherence to different substrates and the chemical stability in artificial saliva at 30 C have been studied. The biocide activity against a Gram-negative bacterium (Escherichia coli) has been determined. It has been proved that this biocide coating also promotes the precipitation of hydroxyapatite. © 2013 Elsevier B.V., This study has been supported by the CSIC Project Reference Number 201360E012 and by the Spanish Ministry of Science and Innovation MAT2012-38645.

Two types of antimicrobial glass fibers containing ZnO and CaO, with diameters ranging from tens of nanometers to 1 m, were successfully fabricated by a laser spinning technique. The antimicrobial performance was corroborated according to ISO 20743:2013, by using gram-negative (Escherichia coli) and gram-positive (Streptococcus oralis, Streptococcus mutans and Staphylococcus aureus) bacteria, and yeast (Candida krusei) (more than 3 logs of reduction). The metabolic activity and endosomal system of eukaryotic cells were not altered by using eluents of CaO glass submicrometric fibers and ZnO fibers at 1 : 10 dilution as cellular media (viability rates over 70%). A dental material was functionalized by embedding ZnO nanofibers above the percolation threshold (20% wt), creating a three-dimensional (3D) fiber network that added an antimicrobial profile. This new ZnO glass fiber composite is proved non-cytotoxic and preserved the antimicrobial effect after immersion in human saliva. This is the first time that a fiber-reinforced liner with strong antimicrobial-activity has been created to prevent secondary caries. The potential of developing new fiber-reinforced composites (FRCs) with antimicrobial properties opens up an extensive field of dental applications where most important diseases have an infectious origin.

This is an open-access article distributed under the terms of the Creative Commons Attribution License.-- et al., The objective of the present study is to evaluate bone loss at implant abutments coated with a soda-lime glass containing silver nanoparticles subjected to experimental peri-implantitis. Five beagle dogs were used in the experiments, 3 implants were installed in each quadrant of the mandibles. Glass/n-Ag coted abutments were connected to implant platform. Cotton floss ligatures were placed in a submarginal position around the abutment necks and the animals were subject to a diet which allowed plaque accumulation, and after 15 weeks the dogs were sacrificed. Radiographs of all implant sites were obtained at the beginning and at the end of the experimentally induced peri-implantitis. The radiographic examination indicated that significant amounts of additional bone loss occurred in implants without biocide coating, considering both absolute and relative values of bone loss. Percentages of additional bone loss observed in implants dressed with a biocide coated abutment were about 3 times lower (p, This work was supported by the Spanish Ministry of Science and Innovation under the project MAT2009-14542-C02-01 and Nanoker Research SL. BC thanks the Consejo Superior de Investigaciones Científicas JAE-Doc Program for a postdoctoral contract.

Incorporation of silver nanoparticles enhances the biocide functionality of Ag supported kaolinite/metakaolite materials. In this regard, structural evolution of supports in the presence of silver nanoparticles is investigated. For this purpose, 27Al and 29Si magic-angle-spinning nuclear magnetic resonance spectroscopy was applied to investigate the bonding between silver nanoparticles and kaolinite/metakaolin materials. The incorporation of silver nanoparticles, following a chemical or thermal reduction, does not change the structure of kaolin, whereas in the case of metakaolin, a preferential interaction with tetrahedral sheets was observed and some stabilization of hexacoordinated aluminium is favoured.

The purpose of the present work was to explore the removal of three polycyclic aromatic hydrocarbons (naphthalene, fluorene and acenaphtene) (PAHs) from aqueous solution onto an activated carbon. The adsorption performance of these compounds (both kinetic and equilibrium) has been discussed in terms of their chemical and physical properties. The results showed that the rate of adsorption was strongly dependent on the molecular size of the hydrocarbons. Thus, for example, steric hindrances associated with acenaphthene inhibited the accessibility of this compound to the high-energy sites. Under equilibrium conditions, the uptake seemed to be governed by the carbon-PAH affinity, as the lowest uptake was obtained for naphthalene which displayed the fastest adsorption rate. The interactions between the studied pollutants and the activated carbon seemed to be controlled by two factors, viz. aromaticity and water solubility. As a general rule, the higher the number of aromatic rings in the polycyclic hydrocarbon, the more favoured the adsorbate—carbon interactions. Analysis of the carbon after adsorption of the studied hydrocarbons indicated that the accessibility restrictions to the porosity of the carbon can also lead to weaker interactions with the activated carbon., The authors acknowledge the financial support of the Spanish MICINN (CTM2008-01956) and CSIC (200980I131). M.H. thanks CSIC for her JAE-Doc research contract.

7 páginas, 6 figuras, 2 tablas., Two different methods to obtain silver nanoparticles supported on kaolin crystals have been performed: the first one followed a thermal reduction and the second one a chemical reduction. In both cases, the silver nanoparticles with two different average particles size (ca.12 and 30 nm) were perfectly isolated and attached to the surface of the kaolin plates. The silver nanoparticles were localized mainly at the edge of the single crystal plates, the hydroxyl groups being the main centres of adsorption. The samples were fully characterized by XRD, UV–vis spectroscopy and TEM. The antimicrobial benefits of the composites were evaluated as antibacterial against common Gram-positive and Gram-negative bacteria, and antifungal activity against yeast. The results indicated a high antimicrobial activity for Escherichia coli JM 110 and Micrococcus luteus, while being inactive against yeast under our experimental conditions. The chemical analysis of Ag in the fermentation broths show that only a small portion of metal (, The authors acknowledge financial support from the Spanish Ministry of Science and Innovation (Bio2008-03683) and funding from the ITMA-CSIC Research Cooperative Project.

The preparation of activated carbons from bean pods waste by chemical (K(2)CO(3)) and physical (water vapor) activation was investigated. The carbon prepared by chemical activation presented a more developed porous structure (surface area 1580 m(2) g(-1) and pore volume 0.809 cm(3) g(-1)) than the one obtained by water vapor activation (258 m(2) g(-1) and 0.206 cm(3) g(-1)). These carbons were explored as adsorbents for the adsorption of naphthalene from water solutions at low concentration and room temperature and their properties are compared with those of commercial activated carbons. Naphthalene adsorption on the carbons obtained from agricultural waste was stronger than that of carbon adsorbents reported in the literature. This seems to be due to the presence of large amounts of basic groups on the bean-pod-based carbons. The adsorption capacity evaluated from Freundlich equation was found to depend on both the textural and chemical properties of the carbons. Naphthalene uptake on biomass-derived carbons was 300 and 85 mg g(-1) for the carbon prepared by chemical and physical activation, respectively. Moreover, when the uptake is normalized per unit area of adsorbent, the least porous carbon displays enhanced naphthalene removal. The results suggest an important role of the carbon composition including mineral matter in naphthalene retention. This issue remains under investigation.

13 pages., A commercial activated carbon was systematically modified by heat treatment at 450°C and 850°C to obtain a series of carbons with various oxygen contents, porous structures and surface functionalities. The carbons were used to investigate the role of adsorbent properties on the removal of naphthalene from aqueous solution. The results confirmed that the adsorption of naphthalene depended strongly on the pore-size distribution of the adsorbent. DTG analysis of the exhausted samples indicated that adsorption forces were stronger in carbons with pores of dimensions close to those of naphthalene. Functionalization of the carbon also influenced its overall adsorption capacity, with uptake being favoured in carbons of a basic nature. The hydrophilic character of the carbons gave rise to strong water competition due to increasing polarity in the adsorbents. This polarity created hydration clusters that reduced the accessibility and affinity of naphthalene molecules to the inner pore structure.

A new family of non-toxic biocides based on low melting point (1250°C) transparent glasses with high content of ZnO (15–40wt%) belonging to the miscibility region of the B2O3-SiO2-Na2O-ZnO system has been developed. These glasses have shown an excellent biocide activity (logarithmic reduction >3) against Gram- (E. coli), Gram+ (S. aureus) and yeast (C. krusei); they are chemically stable in different media (distilled water, sea-like water, LB and DMEN media) as well as biocompatible. The cytotoxicity was evaluated by the Neutral Red Uptake using NIH-3T3 (mouse embryonic fibroblast cells) and the cell viability was >80%. These new glasses can be considered in several and important applications in the field of inorganic non-toxic biocide agents such as medical implants, surgical equipment, protective apparels in hospitals, water purifications systems, food packaging, food storages or textiles., This study has been supported by Consejo Superior de Investigaciones Cientificas (CSIC) project reference number 201360E012 and by the Spanish Ministry of Science and Innovation MAT2012-38645. C. Prado and B. Cabal acknowledge financial support from JAE-Doc program (CSIC, cofounded by FSE).

Resumen del póster presentado a la Conferencia: Nanotech: Advanced Materials & Applications celebrada del 15 al 18 de junio de 2014 en Washington DC (USA).