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Medical Materials and Medical Implant DesignMedical Materials and Medical Implant DesignPolymer engineering, additive manufacturing, cell-based medical engineering, IoT and materials

n The Chair of Medical Materials and Medical Implant Design is significantly involved in the Master’s program Medical Technology and Engineering. In research and teaching, the team deals with production technologies and materials for medical technology, with a particular focus on plastics technology.

The year 2017 was marked in research and teaching mainly by an intensification of polymeric additive manu­facturing. Driven by the approval of an EXIST Transfer of Research grant, 3D printers for demanding medical materials (PEEK, TPE, silicone) could be developed. In addition, the chair has taken over a coordinating role in the Community of Practice ‘IoT & Materials’ of the Zentrum Digitalisierung.Bayern. Furthermore, the foun­dation of three startups was realized and supported in cooperation with UnternehmerTUM (KUMOVIS GmbH, inveox GmbH, essentim GmbH). International cooperation has been established with MIT (Soft Robotics), TUM Asia (medical polymer technology) and Addis Ababa University (medtech for developing countries).

Process chain for automated generation of intraoral guiding plates

Baby suffering from cleft lip and palate treated with an intraoral guiding plate

Individualized Medical Technology – Palate Plates for the Treatment of Cleft Lip and Palate

Cleft lip and palate represents with an incidence of 1 in 700 newborns the most common craniofacial birth impairment. Without treatment the malformation would harm breast feeding, hinder voice and auditory develop­ment, and the visual appearance would remain distorted. As a presurgical treatment nasoalveolar molding (NAM) addresses reduction of the cleft gap and improvement of nasal symmetry by use of an intraoral guiding plate, which encourages the alveolar segments to grow towards each other. In the project RapidNAM a system was developed

to design the NAM plates within 10 minutes in a fully automated process based on just a single impression taken initially. The plates are manufactured additively. So far already six patients have been treated with such automatically generated NAM plate sets.

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Polymer Technology – Novel Plastics with Germicidal Effect

Germs are found in all areas of everyday life and can lead to dangerous infections. To reduce the risk of infection in sanitary facilities and hospitals, surfaces with antimicrobial properties can be used. The aim of the project AntiMik is to obtain polymer compounds with antimicrobial properties for the preventive reduction of microorganisms in the health care sector. Nano­scale, photocatalytically active titanium dioxide (TiO2) is incorporated into different polymer matrix systems. The TiO2 induces radicals on the surface that have the potential to kill germs. The objective of this project is to identify and process matrix­filler com­binations with a high germ reduction rate and resistance against material ageing.

Agar plate with grown bacteria colonies to assess antimicrobial polymer compounds

Approximately 1 billion people live in so­called least devel­oped countries (LDC). Driven by the initiative of the students, the project ‘MedTech for LDC’ creates a knowledge and cooperation basis for the development of medical devices that can be manufactured and marketed under the condi­tions in LDCs. In a first approach, a cooperation was established with Addis Ababa University and the NGO Cheshire Services Ethiopia, which provide the children of the poorest with simple prostheses.

Robust 3D-printed prosthesis for use in least developed countriesStudent Fabian Jodeit with his Ethiopian cooperation partners

Medtech in Least Developed Countries – Robust 3D Printed Prostheses for the Poorest

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The high priority of functioning, aesthetically pleasing teeth motivates the continuous optimization of dental prostheses and the materials used for them. As an alternative to currently used ceramics, thermoplasts or combinations of a ceramic framework and a polymeric veneer are being used increasingly. In order to exploit the advantages of thermoplasts and at the same time to meet the mechanical and optical requirements of dentures, the TheverTech project in cooperation with the Poliklinik für Zahnärztliche Prothetik of LMU Munich has developed a new method for veneering ceramic crowns and bridges with high­performance thermoplasts (e.g. PEEK).

Ceramic bridge (top) with thermoplastic veneer (bottom)

Dental Technology – Novel Dental Veneers Made of Thermoplasts

The research group ‘IoT & Polymers’ systematically investigates the interaction between plastics and their pro­cessing on the one hand and IoT electronics on the other. Use in the medical environment places special demands on IoT­augmented plastic parts. These include strains from sterilization or disinfection processes as well as the use in the organism’s aqueous environment with a risk of short­circuit and corrosion. Research focuses on inte­gration strategies with coatings and casting compounds for cushioning mechanical forces in the injection molding process, surface technologies for optimizing composite materials with regard to conformal integration, and the investigation of the influence of plastics on electromag­netic waves. Suitable materials for the realization of plastic­electronic composites are identified with regard to

Smart Technology – Integration of IoT Electronics into Medical Plastic Parts

Bioprotective conformal polymeric encapsulation of IoT electronics

their biocompatibility and bioprotective effect (prevention of the release of toxic and allergenic substances).

Platelet rich plasma (PRP) is generated from a patient’s own blood by centrifugation. Platelets contain growth fac­tors, which guide tissue regeneration and enhance heal­ing. Thus, PRP can be therapeutically applied to wound sites to support the body’s healing process. However, in current systems numerous manual steps in the manufac­turing processes lead to reduced reproducibility of the quality of this patient’s own therapeutic agent. Therefore, a centrifugation system enabling fully automated pro­duction of PRP has been developed and is now being launched on the market. Optimization and expansion of the system to produce various blood products offering a broad therapeutic field is currently under investigation. Automated system for production of patient’s own blood products for

therapeutic use

Regenerative Medicine – Automated Production of Patient’s Own Therapeutic Blood Products

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Laboratory medicine is often given little consideration in the context of health care because it lacks direct patient contact. Nevertheless, it is very significant in terms of health economics. In addition to tasks in classical diag­nosis (e.g. blood and tissue examinations), laboratory medicine also plays a major role in future­oriented pro­cedures such as stem cell or autologous blood therapy. Outside of high­tech blood analysis laboratories, many activities in biomedical labs are still performed by hand at high cost and risk of human errors (e.g. sample confusion, miss­handling). The aim of the research area ‘Lab 4.0’ is therefore the development of highly function integrated, autonomous and process­monitored systems for the cultivation of biological samples.

Additive manufactured miniaturized bioreactor with integrated wall heating for biocompatibility tests

Lab 4.0 – Highly Function Integrated Smart Bioreactors

Additive manufacturing (3D­printing) is seen as a disrup­tive technology in production. Especially for medical appli­cations additive manufacturing will be a key technology to produce small series products as well as individualized implants. Starting as a student project in 2015, the team AM Medical developed a printer for the processing of established medical­grade plastics based on FFF (fused filament fabrication). The team is now funded by EXIST Transfer of Research and recently founded the KUMOVIS GmbH. The KUMOVIS printer enables an economically feasible processing of medical­grade high performance plastics such as PEEK and flexible plastics (e.g. TPE). Additionally the team is working on the fabrication of filaments to guarantee a complete production process chain fulfilling medical standards like biocompatibility and the absence of particles.

KUMOVIS at Formnext, Europe’s most important fair for additive manufacturing

KUMOVIS PEEK printer for additive manufacturing of medical devices.

Spin-off KUMOVIS – 3D Printer for Medical Applications

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Prof. Dr. Tim C. Lüth

Dr. Markus Eblenkamp

Contactwww.medtech.mw.tum.demarkus.eblenkamp@tum.dePhone +49.89 289.16700

ManagementProf. Dr. Tim C. LüthDr. Markus Eblenkamp

AdministrationSusanne Wiedl

Research ScientistsFranz Bauer, M.Sc.Sarah Burkhardt, M.Sc.Katharina Düregger, M.Sc.Theresa Fischer, M.Sc.Stefan Fischer, M.Sc.Johannes Gattinger, M.Sc.Dr.­Ing. Miriam HaerstAlexander Henhammer, M.Sc.Valerie Köhler, M.Sc.Stefan Leonhardt, M.Sc.Sebastian Pammer, M.Sc.Christin Rapp, M.Sc.Dipl.­Ing. Andreas RobeckTim Scherzer, M.Sc.Dipl.­Ing. Valerie WernerDipl.­Ing. Matthias Zeppenfeld

Technical StaffMarkus Ahrens, B.Sc.Uli Ebner (Master)Georg LerchlIlse SchunnFlorian HuberSahel YusofzaiFabian Hüttinger

Research Focus■n Medical materials■n Polymer technology■n Machine and process technology■n Cell­based medical engineering■n Implantology

Competence■n Polymer processing■n Additive manufacturing■n Material testing, incl. biocompatibility■n Bioreactor designing■n Blood processing

Infrastructure■n Technical lab (CNC milling machine, water jet cutting, etc.)

■n Bio lab (biocompatibility and sterility testing)

■n Polymer lab (injection molding, extrusion, compounding, testing)

■n 3D lab (DLP, FFF, multijet printing)■n Electronic lab (anechoic chamber, micrograph analysis, etc.)

Courses■n Introduction in Medical and Polymer Technology

■n Biocompatible Materials■n Plastics and Plastic Processing■n Trends in Medical Engineering■n Vascular Systems

Selected Publications 2017■n Bauer, F. X., Schönberger, M., Gat­tinger, J., Eblenkamp, M., Winter­mantel, E., Rau, A., Güll, F. D., Wolff, K.­D., Loeffelbein, D. J.: RapidNAM: generative manufacturing approach of nasoalveolar molding devices for presurgical cleft lip and palate treatment. Biomedical Engineering/Biomedizinische Technik, 62 (4), 2017, 407­414

■n Bodden, L., Nina Lümkemann, N., Köhler, V., Eichberger, M., Stawarczyk, B.: Impact of the heating/quenching process on the mechanical, optical and thermodynamic properties of polyetheretherketone (PEEK) films. Dental Materials, 33 (12), 2017, 1436­1444

■n Düregger, K., Frenzel, S., Eblenkamp, M.: Autologous fibrin glue: automated production and adhesive quality. Current Directions in Biomedical Engineering 3 (2), 2017, 397­400

■n Eblenkamp, M., Düregger, K., Leon­hardt, S.: Biomimicry – One Layer at a Time: High­Function Integrated Plastics Systems for the Cell­Based Laboratory Medicine. Kunststoffe international, 6­7, 2017, 44­46

■n Werner, V., Müller, T., Qi, X., Zeppen­feld, M., Eblenkamp, M.: Fertigungs­strategien zur funktions erhaltenden und biokompatiblen Integration von IoT­Bauteilen in medizinisch relevante Kunststoffe. MikroSystemTechnik Kongress 2017, München, 2017