1. Division of Conservative Dentistry and Periodontology, University Clinic of Dentistry, Medical University of Vienna, 1090 Vienna, Austria
2. Department of Periodontology, School of Dental Medicine, University of Bern, 3010 Bern, Switzerland
3. Center of Clinical Research, University Clinic of Dentistry, Medical University of Vienna, 1090 Vienna, Austria
4. Austrian Research Group for Regenerative and Orthopedic Medicine (AURROM), 1050 Vienna, Austria
5. Austrian Society of Regenerative Medicine, 1010 Vienna, Austria