Significantly improved glass ceramics
The demands placed on a dental prosthesis are high: it should look natural, endure accidental biting on cherry pits – and if possible, the patient should be able to remain in the dentist's chair while the dental prosthesis is individually milled and inserted.
Until the development of the Fraunhofer ISC solution, glass ceramics were considered to have reached their maximum potential.
Piotr Banczerowski / Fraunhofer-Gesellschaft
Dr. Bernhard Durschang and Dr. Jörn Probst of the Fraunhofer Institute for Silicate Research ISC have developed such a dental prosthesis and have been awarded the Fraunhofer "Human-Centered Technology" prize.
The tooth is badly damaged and must be repaired. Dentists use a variety of materials, including glass ceramics. They look most natural, and the dentist can also finish a glass-ceramic prosthesis directly in the practice.
To do this, the dentist first records the situation of the teeth in the patient's mouth using a pencil camera, software calculates the individual CAD data, and a milling machine cuts the crown automatically and precisely via CAM. The blank is then hardened at a temperature of at least 800 degrees Celsius, which is a time-consuming work step.
In addition, the color of the dental crown changes as it is being heated up. It is therefore possible that the dental bridge does not perfectly match the color of the rest of teeth: Then it has to be modified with a veneer.
The glass ceramics were considered to have reached their maximum potential
Dentists and patients alike want a product that can be individually adapted at such a pace that the patient can wait for it in the dentist's chair – this is also referred to as chairside treatment. In addition, the dental prosthesis should be as strong as possible in order to be able to withstand the strain in the long term. With current glass ceramics, further improvements were no longer possible and considered to have reached their maximum potential.
However, Dr. Bernhard Durschang and Dr. Jörn Probst from the Fraunhofer Institute for Silicate Research ISC in Würzburg have now developed exactly such a dental prosthesis, together with the companies VITA Zahnfabrik H. Rauter GmbH & Co. KG and DeguDent GmbH. For their achievement, the two Fraunhofer researchers were awarded the Fraunhofer Prize "Human-Centered Technology".
"At more than 500 MPa, our glass ceramic is much stronger and more robust than conventional glass ceramics, which only reach around 350 MPa," says Probst, who has been responsible for the health application area at the Fraunhofer ISC since 2002. "In addition, post-curing in the furnace is no longer necessary. And: glass ceramics in all different color nuances with their enamel-like translucency have an excellent visual appearance. The prosthesis can be optimally chosen according to the patient's tooth color and looks completely natural."
Thinking outside of the box led to the desired results
Yet, how did the researchers manage to elicit so many improvements from a material that is considered to have reached its full potential? Glass ceramics consist of an amorphous glassy phase and a crystalline portion. So far, researchers have tried to push the proportion of the crystalline phase as high as possible – after all, it was the crystalline phase that provided the strength. However, the two scientists at the Fraunhofer ISC broke with conventional wisdom.
"Instead, we have turned to the properties of the glass phase – and thus achieved something amazing," explains Durschang, who has been developing glasses and glass ceramics at the Fraunhofer ISC since 1996. "Adding various metal oxides to the amorphous portion increases its strength. Thus the amorphous portion of the unpleasant residual glass that one wants to get rid of is transformed into a useful portion that even increases the overall strength."
The project extended far beyond the actual material development. The two partner companies received everything from a single source: from the initial solution idea to the CE-certified production plant. In the meantime, this new type of glass ceramic is already in use by many dentists. The annual revenue of these glass ceramics at the two partner companies is already in the double-digit million range – annual growth rates of around 20 percent are expected in the coming years.
This press release is published by the Fraunhofer-Gesellschaft
More Information about the Fraunhofer Research Awards: https://www.fraunhofer.de/en/about-fraunhofer/excellence-in-research/fraunhofer-...
Press release and more information on Fraunhofer ISC's website: https://www.isc.fraunhofer.de/en/press-and-media/press-releases/new-teeth-highly...
https://youtu.be/I2tbCgZkwPI The video "New teeth: Highly rigid – and ready for immediate use" is available on Fraunhofer's youtube channel
Dipl.-Geophys. Marie-Luise Righi | Fraunhofer-Institut für Silicatforschung ISC
21.08.2019 | Harvard John A. Paulson School of Engineering and Applied Sciences
New 3D interconnection technology for future wearable bioelectronics
15.08.2019 | Institute for Basic Science
Since their experimental discovery, magnetic skyrmions - tiny magnetic knots - have moved into the focus of research. Scientists from Hamburg and Kiel have now been able to show that individual magnetic skyrmions with a diameter of only a few nanometres can be stabilised in magnetic metal films even without an external magnetic field. They report on their discovery in the journal Nature Communications.
The existence of magnetic skyrmions as particle-like objects was predicted 30 years ago by theoretical physicists, but could only be proven experimentally in...
Theoretical physicists at Trinity College Dublin are among an international collaboration that has built the world's smallest engine - which, as a single calcium ion, is approximately ten billion times smaller than a car engine.
Work performed by Professor John Goold's QuSys group in Trinity's School of Physics describes the science behind this tiny motor.
Together with the University of Innsbruck, the ETH Zurich and Interactive Fully Electrical Vehicles SRL, Infineon Austria is researching specific questions on the commercial use of quantum computers. With new innovations in design and manufacturing, the partners from universities and industry want to develop affordable components for quantum computers.
Ion traps have proven to be a very successful technology for the control and manipulation of quantum particles. Today, they form the heart of the first...
Experimental progress towards engineering quantized gauge fields coupled to ultracold matter promises a versatile platform to tackle problems ranging from condensed-matter to high-energy physics
The interaction between fields and matter is a recurring theme throughout physics. Classical cases such as the trajectories of one celestial body moving in the...
Soft robots have a distinct advantage over their rigid forebears: they can adapt to complex environments, handle fragile objects and interact safely with humans. Made from silicone, rubber or other stretchable polymers, they are ideal for use in rehabilitation exoskeletons and robotic clothing. Soft bio-inspired robots could one day be deployed to explore remote or dangerous environments.
Most soft robots are actuated by rigid, noisy pumps that push fluids into the machines' moving parts. Because they are connected to these bulky pumps by tubes,...
16.08.2019 | Event News
14.08.2019 | Event News
12.08.2019 | Event News
23.08.2019 | Medical Engineering
23.08.2019 | Power and Electrical Engineering
23.08.2019 | Life Sciences