1. Department of Oral and Maxillofacial SurgeryMedical Center – University of FreiburgFaculty of MedicineUniversity of Freiburg Germany
2. Department of Oral ImplantologyAcademisch Centrum Tandheelkunde Amsterdam (ACTA) Amsterdam the Netherlands
3. Department of OrthodonticsUniversity Medical Center GroningenUniversity of Groningen Groningen the Netherlands
4. W.J. Kolff Institute of Biomedical Engineering and Materials Science Groningen the Netherlands
5. Institute for Medical Biometry and StatisticsFaculty of MedicineUniversity of Freiburg Freiburg Germany
6. Maurice H. Kornberg School of DentistryTemple University Philadelphia Pennsylvania