1. Department of Dental Materials and Biomaterials Research, RWTH Aachen University Hospital, Aachen, Germany.
2. Institute for Biomedical Engineering, Biointerface Group, Helmholtz Institute of Biomedical Engineering, RWTH Aachen University Hospital, Aachen, Germany.
3. Institute of Pathology, RWTH Aachen University Hospital, Aachen, Germany.
4. IZKF Aachen, RWTH Aachen University Hospital, Aachen, Germany.