Piezoceramic stack activator accelerates root canal healing

DRESDEN/ROSTOCK, Germany: A common challenge you face during root canal treatment is the frequent blockage of the rotating file, which requires regular cleaning. Addressing this issue, researchers from the Fraunhofer Institute for Ceramic Technologies and Systems (IKTS) in Dresden and the Department of Dentistry at the Rostock University Medical Center have developed a piezoceramic stack actuator that enables faster and more efficient patient procedures.

In Germany, approximately seven million root canal treatments are performed annually. Despite the fact that dental files are made of a super-elastic nickel-titanium alloy, there is a high risk that these files will break under pressure, necessitating frequent removal and thorough cleaning.

The newly developed device overlaps file rotation with axial vibration in the ultrasonic frequency range. The goal is to reduce the risk of file breakage and improve the effectiveness of root canal treatments.

Advantages of Piezoceramic Stack Actuator

Dr. Holger Neubert, head of the Department of Smart Materials and Systems at Fraunhofer IKTS, said in a press release: “By overlaying rotation with axial vibration, the file clogs less quickly, which means it does not need to be cleaned. often. Dentists can then focus much more on their complex root canal work. The risk of the file being hacked is also reduced.”

He added: “The basic idea of combining the two movements of the dental file came from the experts at the Department of Dentistry at the Rostock University Medical Center. We used piezoceramic stack actuators as the drive element because they are able to meet the specific requirements for vibration amplitude and frequency, size as well as supply voltage.”

Piezoceramic-based actuators offer many benefits. Their compact size and fast and accurate operation make them highly efficient and offer ease of control and minimal heat loss. These actuators consist of multiple layers of segments that collectively amplify displacement, allowing for a design that is small enough to navigate the tightest spaces in a patient’s mouth. In addition, the research team manufactured the stack actuator from lead-free materials, meeting the future requirements of European directive on the restriction of hazardous substances in electrical and electronic equipment.

Dentists at the Rostock University Medical Center tested the new technology on artificial teeth and received positive results.

Dental file with integrated piezoceramic stack actuator. (Image: Fraunhofer IKTS)

Additional medical engineering applications

The newly developed technology holds promise for a range of medical applications beyond dentistry, including applications in diagnostic imaging and cancer treatment. Researchers are exploring its use in low-frequency ultrasound transducers, which offer high penetration depth for tomography. Advances in piezoceramic transducers have led to their miniaturization, allowing up to 2,000 units to be integrated into a standard-sized tomography system. This facilitates high-resolution 3D imaging that is critical for medical diagnosis.

In addition, high-frequency ultrasound transducers are becoming increasingly valuable in fields such as dermatology for their ability to provide accurate images at shallow depths. Further possibilities lie in high-performance ultrasound transducers designed to target and destroy specific areas of tissue with focused sound waves, a technique particularly important in cancer treatment.

“Piezoceramic components can be used in a wide range of applications and, thanks to their compactness and performance, are ideal for medical engineering. We are able to develop customized solutions that fit the needs of individual customers,” emphasized Dr. Neubert.