1. Department for Conservative Dentistry University Hospital of Heidelberg Heidelberg Germany
2. Department for Conservative Dentistry University Hospital Tuebingen Tübingen Germany
3. Institute of Nutritional Medicine University of Hohenheim Stuttgart Germany
4. Department of Nutrition Management and Nutrition Support Team University Hospital Tuebingen Tübingen Germany
5. Institute of Medical Biometry Faculty of Medicine ‐ University of Heidelberg Heidelberg Germany
6. Centre of Laboratory Diagnostics MVZ Clotten Freiburg Germany
7. Department of Operative Dentistry and Periodontology, Faculty of Medicine University of Freiburg Freiburg Germany