1. Clinic of Fixed and Removable Prosthodontics and Dental Material ScienceCenter of Dental MedicineUniversity of Zurich Zurich Switzerland
2. Akademie für Orale ImplantologiePrivate Practice Vienna Austria
3. Aesthetic DentPrivate Practice Szczecin Poland
4. University of Santiago de Compostela Santiago de Compostela Spain
5. University of Connecticut Farmington Connecticut