Shatterproof, resistant to erosion, corrosive media and high temperatures: ceramics are genuine superheroes among materials, also when it comes to their use in medical technology. Thanks to their properties and the right manufacturing process, they can fulfill many wishes on the lists of medical device manufacturers – and some wishes these manufacturers maybe did not even dare to dream of yet.
Andreas Rempp talks in the COMPAMED SUPPLIERS FORUM
On Monday afternoon, the COMPAMED SUPPLIERS FORUM by DeviceMed focused on "High-Performance Ceramics in Medical Technology". COMPAMED-tradefair.com talked to Andreas Rempp about ceramics, how they are made and asked how they can support medical technology in the future.
Mr. Rempp, what do you mean by the term "high-performance ceramics"?
Andreas Rempp: This term refers to ceramics that - thanks to high-quality raw materials and various manufacturing processes that CeramTec specializes in - exhibit unique properties that are not attainable in other materials. For example, they can exhibit a higher degree of rigidity, wear resistance and chemical resistance. Plus they can also exhibit very high stability – that means, the load capacity before the material breaks has been extremely increased. We are able to provide ceramics for use at very high temperatures, as well as ceramics with unique optical or electrical properties. Another interesting aspect is functional properties, as is the case with piezoceramics for example, which expand or contract with electric pulses. This puts high-performance ceramics into a broad class of materials that has major advantages under extreme demands compared to conventional materials like plastics or metals.
Where are they applied in medical technology?
Rempp: We believe the best-known example is the hip joint endoprosthesis, which consists of a tribological pairing of a ceramic ball head and the insert as the counterpart. After implantation, it should ideally maintain its function without any complications for the rest of the patient’s life. Needless to say, an artificial joint is unable to regenerate itself like a natural joint made of cartilage and bone is able to do. However, ceramic is very strong and wear resistant as well as chemically inert and corrosion-resistant, which offers the best conditions for lifetime durability. It also has excellent sliding properties because its surface is well wetted. Our components are produced with high-precision and excellent surface finishing. These properties ensure that ceramic is quickly becoming the standard material used for artificial joints.
How is the material processed for use in an endoprosthesis?
Rempp: The composition is crucial because many of our ceramics are composite materials made of aluminum oxide, zirconium oxide, and other additives for example. Thanks to the right mixture, we achieve the exact properties we desire. The raw materials are first ground, then pressed and pre-molded, subsequently fired at temperatures of over 1,500 degrees and compressed at a pressure of over 1,000 bar. This is followed by intricate postprocessing where we take diamond tools to work the piece into the right shape and surface quality for an endoprosthesis. This intricate procedure is necessary to get excellent material properties. The 100% final inspection of all our components for medical applications is also essential.
What are the trends in ceramic applications in medical technology?
Rempp: Until now, the brittle fracture behavior of ceramics has prevented broader applications. When it comes to metal, there are frequently early warning signs of mechanical overload by way of plastic deformation, whereas ceramics could have brittle fractures "without warning" in case of overloading. So far, this has prohibited many applications for ceramics. We have conducted a lot of research and development to create ceramics that provide sufficient stability and high safety margins and that are as resilient as high strength metals. I believe that ceramics will take over wherever heavy-duty components are needed but metals have drawbacks. One key example is applications that require diagnostic imaging like radiography or magnetic resonance. In this case, metals can disrupt imaging techniques but ceramics do not.
The aforementioned piezoceramics are suitable for a multitude of functional applications, for example, in nozzle systems for inhalers.
We register an increasing demand for materials with improved properties as it pertains to biocompatibility, load capacity and life expectancy and keep receiving new inquiries about particular ceramic components for use in both in and outside the human body. That is why we are certain that we will discover new areas of application based on our extensive material expertise and many years of experience in the medical field.
The interview was conducted by Timo Roth and translated from German by Elena O'Meara. COMPAMED-tradefair.com