Dental and oral surgical treatment should ideally be completed as quickly and painlessly as possible – and with excellent results. To achieve this, even in complex and lengthy procedures, developers of medical technology are constantly working on new solutions. At Furtwangen University, Professor Ulrich Mescheder is conducting research in the field of microsystems technology.
As part of the CoHMed innovation partnership, the physicist Professor Mescheder, Vice President for Research at HFU and Director of the Institute for Microsystems Technology (iMST), is working with his project team on an implantable "distractor." This instrument is used in surgery to "lengthen" bone, i.e., to build bone without using artificial materials. For example, if a patient's jawbone is too narrow, doctors can cut through the bone and insert a distractor. This spreads the bone pieces apart - in tiny increments that must currently be adjusted manually on a daily basis using a screw. "The body fills the resulting gap with what is known as callus fluid, which then hardens and forms new bone material," Mescheder explains. What already sounds rather frightening is at the present time further complicated by the fact that the threaded screw used to push the distractor's surfaces apart over a period of weeks must be externally accessible to doctors.
"A few years ago, therefore, we were approached by medical technology companies who wanted to know if this could be automated," reports Professor Mescheder. To make the procedure more comfortable and, above all, safer for patients, he and his colleagues are working to develop a tiny implantable system that will independently regulate the spreading process. The task is not only to replace the mechanical process of pushing two plates apart by one millimeter per day using tiny components - these components, a battery for instance, must also be "wrapped" and encased in coatings in such a way that any harmful effect on the body can be ruled out. HFU Professor Dr Volker Bucher, also a member of iMST, and his team are carrying out research on this as part of the same project. "An implantable distractor can also be used to customise the treatment of individual patients," says Professor Mescheder. "Currently, doctors spread the bone every day, and after about six months the thing comes out," he describes vividly, "but they never really know what it looks like inside." The implantable version, on the other hand, will have sensors that "feel" how firm the newly formed bone tissue already is - so that treatment can be completed earlier if necessary, at precisely the right time. An automated implanted distractor can also make small movements, a so-called callus massage, that support bone formation.
Creating tiny sensors that can do this is Professor Mescheder's world. The components being developed in the HFU labs are so small that you can't even see them, let alone touch them. "You can take a human hair for comparison," says the scientist. "We're working with sizes that are 50 times, sometimes even a thousand times smaller." Sensors that fit on the tips of needles. Or nanostructures that set off tiny, deliberate "explosions", whose energy in turn powers tiny systems. "I've been doing this for 30 years," Mescheder laughs, "you get used to thinking so small." The parts of the microsystems he works on are becoming smaller and ever more fragile: "We are at the stage where there are only about ten atoms next to each other." He often gets ideas for new research projects from the "macro world" - while riding his bicycle, for example, he came up with the idea of building a nano-sized Velcro fastener. In the meantime, this has also developed into a separate research project.
As part of "CoHMed", the HFU medical technology innovation and transfer partnership, Furtwangen University is one of ten universities nationwide to receive funding under the "Strong Universities of Applied Sciences - Impetus for the Region" programme of the German Ministry of Education and Research. CoHMed is designed to support companies in the region in the development, research, and innovation of future-oriented products. Research projects in the field of intelligent medical instruments, functional surfaces, and biocompatibility, as well as new materials and their processing, have already been successfully launched. Further projects in the area of digitalisation of operations and medical technology manufacturing will follow.
The implantable distractor, like many research projects, has a long way to go before it will be available to doctors and patients. Multiple studies and approval processes still lie ahead. Professor Mescheder is used to taking a small-scale view of things, but here he sees the time-scale as being larger: "It's always a long road. With our distractor I expect it to take a few more years yet."