1. Department of Prosthodontics, Faculty of Odontology; Malmö University; Malmö Sweden
2. Department of Oral and Maxillofacial Prosthodontics and Oral Implantology, Institute of Health Biosciences; The University of Tokushima Graduate School; Tokushima Japan
3. Institut Straumann AG; Basel Switzerland
4. Department of Periodontics; New York University College of Dentistry; New York NY USA