1. Department of Oral and Maxillofacial Surgery; Karolinska University Hospital; Stockholm Sweden
2. Department of Oral and Maxillofacial Surgery; Umeå University; Umeå Sweden
3. Department of Oral & Maxillofacial Surgery and Periodontics; Faculty of Dentistry of Ribeirão Preto; University of São Paulo; Ribeirão Preto Brazil
4. Department of Oral and Maxillofacial Surgery; Sahlgrenska Academy; Gothenburg University; Göteborg Sweden
5. Department of Otorhinolaryngology; Karolinska University Hospital; Stockholm Sweden