1. Department of Oral Surgery; Universitätsklinikum Düsseldorf Germany
2. Faculty of Odontology; Universidad Complutense of Madrid; Madrid Spain
3. Department of Prosthodontics and Biomaterials; Center for Implantology; Medical Faculty; RWTH Aachen University; Aachen Germany
4. Department of Reconstructive Sciences; University of Connecticut School of Dental Medicine; Farmington CT USA
5. Camlog Foundation; Basel Switzerland