Nanocoatings Reduce Dental Implant Bacterial Infection By 97%

According to the American Academy of Implant Dentistry (AAID), 15 million Americans have crown or bridge replacements and three million have dental implants – with this latter number rising by 500,000 a year. The AAID estimates that the value of the American and European market for dental implants will rise to $4.2 billion by 2022. Dental implants are a successful form of treatment for patients, yet according to a study published in 2005, five to ten per cent of all dental implants fail. The reasons for this failure are several-fold – mechanical problems, poor connection to the bones in which they are implanted, infection or rejection. When failure occurs the dental implant must be removed. The main cause for dental implant failure is peri-implantitis. This is the destructive inflammatory process affecting the soft and hard tissues surrounding dental implants. This occurs when pathogenic microbes in the mouth and oral cavity develop into biofilms, which protects them and encourages growth. Peri-implantitis is caused when the biofilms develop on dental implants.

A research team comprising scientists from the School of Biological and Marine Sciences, Peninsula Schools of Medicine and Dentistry and the School of Engineering at the University of Plymouth, have joined forces to develop and evaluate the effectiveness of a new nanocoating for dental implants to reduce the risk of peri-implantitis.

dentistIn this cross-Faculty study we have identified the means to protect dental implants against the most common cause of their failure. The potential of our work for increased patient comfort and satisfaction, and reduced costs, is great and we look forward to translating our findings into clinical practice,”  commented Professor Christopher Tredwin, Head of Plymouth University Peninsula School of Dentistry.

In the study, the research team created a new approach using a combination of silver, titanium oxide and hydroxyapatite nanocoatings. The application of the combination to the surface of titanium alloy implants successfully inhibited bacterial growth and reduced the formation of bacterial biofilm on the surface of the implants by 97.5 per cent.

Not only did the combination result in the effective eradication of infection, it created a surface with anti-biofilm properties which supported successful integration into surrounding bone and accelerated bone healing.

The results of their work are published in the journal Nanotoxicology.

Source: https://www.plymouth.ac.uk/

Japan Bets On Hydrogen As A Green Energy Source

Hydrogen gas is a promising alternative energy source to overcome our reliance on carbon-based fuels, and has the benefit of producing only water when it is reacted with oxygen. However, hydrogen is highly reactive and flammable, so it requires careful handling and storage. Typical hydrogen storage materials are limited by factors like water sensitivity, risk of explosion, difficulty of control of hydrogen-generation.

alstom-hydrogen-electric-train Hydrogen gas can be produced efficiently from organosilanes, some of which are suitably air-stable, non-toxic, and cheap. Catalysts that can efficiently produce hydrogen from organosilanes are therefore desired with the ultimate goal of realizing safe, inexpensive hydrogen production in high yield. Ideally, the catalyst should also operate at room temperature under aerobic conditions without the need for additional energy input. A research team led by Kiyotomi Kaneda and Takato Mitsudome at Osaka University have now developed a catalyst that realizes efficient environmentally friendly hydrogen production from organosilanes. The catalyst is composed of gold nanoparticles with a diameter of around 2 nm supported on hydroxyapatite.

The team then added the nanoparticle catalyst to solutions of different organosilanes to measure its ability to induce hydrogen production. The nanoparticle catalyst displayed the highest turnover frequency and number attained to date for hydrogen production catalysts from organosilanes. For example, the  converted 99% of dimethylphenylsilane to the corresponding silanol in just 9 min at room temperature, releasing an equimolar amount of hydrogen gas at the same time. Importantly, the catalyst was recyclable without loss of activity. On/off switching of hydrogen production was achieved using the nanoparticle catalyst because it could be easily separated from its organosilane substrate by filtration. The activity of the catalyst increased as the nanoparticle size decreased.

A prototype portable hydrogen fuel cell containing the nanoparticle catalyst and an organosilane substrate was fabricated. The fuel cell generated power in air at room temperature and could be switched on and off as desired.

Generation of hydrogen from inexpensive organosilane substrates under ambient conditions without additional energy input represents an exciting advance towards the goal of using hydrogen as a green energy source.

Source: https://www.eurekalert.org/
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http://www.nature.com/

Nanostructures For Hip and Knee Implants.

Scientists from the Research Center for Advanced Materials (CIMAV) in Mexico look for nanostructures that allow compatibility between metal, human bone tissues. Various scientific projects performed at the Cimav, Unit Monterrey, in the north of Mexico, aimed at one goal: conducting research and apply the knowledge in the development of biomedical implants, since the ones existing in the domestic market come generally from foreign manufacture. Currently this center, part of the National Council for Science and Technology (CONACYT) and located at the Park of Research and Technological Innovation (PIIT), works on the study of novel materials, coating systems and specific properties to use in the manufacture of hip and knee implants, and, in the future, of dental parts. It is the combination of research focused on nanostructured materials with biocompatible and antibacterial properties. In this regard, Ana Maria Arizmendi Morquecho, Cimav scholar, explains that the challenge is to find appropriate measures to improve the compatibility of a metal structure with the chemical composition of bone tissue and human bone’s nanostructures.
ceramic material compatible with the boneWe use a ceramic material which is compatible with the bone, in this case hydroxyapatite, which is used as a matrix and nanoparticles from other materials are used to reinforce it and provide improvements to the bicompatibility, joint wear and mechanical properties” , explains Arizmendi Morquecho
The biocompatibility is the ability of a material to be in contact with a living being without adverse effects, therefore represents one of the most important properties in the manufacture of a biomedical implant. Currently the knee and hip implants are complex systems made of titanium alloy substrates, which require a coating compatible with bone tissue and physiological fluids using nanotechnology; to achieve this intermediate coating deposition techniques of new synthesized materials are used”.

Source: http://www.cimav.edu.mx/

Nano Toothpaste Is A Cavity Filter, Bacteria Killer

There are 3 main toothpaste ingredients that may be made of nano-sized particles.

Hydroxyapatite, cavity filler. Hydroxyapatite is a lattice of calcium found naturally in teeth and bones. It helps prevent tooth pain associated with sensitivity. Coating the teeth and slipping into tiny cracks, it breaks down in response to acid before your enamel does, protecting the teeth from decay and cavities+. Hydroxyapatite also provides a source of calcium and phosphate ions which, combined with fluoride, help to remineralise the tooth surface.

Silver, bacteria killer. Silver nanoparticles are proven to have antibacterial properties, reducing the risk of gum disease and bad breath caused by bacteria in the mouth. Its distribution in toothpaste remains largely limited to manufacturers based in Asia, though such products can be purchased online. Like titanium dioxide, it is widely used in a number of other products, including clothing and plasters.

Titanium dioxide, whitener. Titanium dioxide is an intensely white pigment. It has a high refractive index, which means it scatters light to create a very white product. Titanium dioxide is widely used in toothpaste, but often the particles used are not small enough to be defined as nanoparticles.

toothpaste
Since July 2013, EU cosmetics regulation has demanded that all nanoparticles are labelled on the ingredient list.

“Silica particles are found in many food stuffs and, in fact, nanosilica particles have been put into cosmetics and household products for more than 40 years People just aren’t aware of this, because back then no one talked about nanotechnology.” explains Dr Robert Hill, from Queen Mary University of London.
Source; http://www.theguardian.com/