1. Clinic Department of Operative Dentistry, Periodontology and Preventive Dentistry, Saarland University, Homburg, Germany
2. Oral Surgery Clinic, German Armed Forces Central Hospital; Koblenz, Germany
3. Institute of Medical Microbiology and Hygiene, Department of Hospital Hygiene, Saarland University, Homburg, Germany
4. University Children’s Hospital, Saarland University Medical Center, Homburg, Germany
5. Chair of Synoptic Dentistry, Saarland University, Homburg, Germany