[1] Univ Granada, Sch Dent, Oral Surg & Implant Dent Dept, Granada, Spain
[2] Univ Michigan, Sch Dent, Dept Periodont & Oral Med, Ann Arbor, MI 48109 USA
[3] Inst Postgrad Educ, Dept Oral & Maxillofacial Surg, Jonkoping, Sweden
[4] Univ Bristol Dent Hosp & Sch, Bristol, Avon, England
[5] Univ Copenhagen Hosp, Rigshosp, Dept Oral & Maxillofacial Surg, DK-2100 Copenhagen, Denmark
[6] Univ Milan, Policlin Milano, Fdn IRCSS Ca Granda Osped Maggiore, Dept Implantol, Milan, Italy
[7] German Fed Armed Forces Hosp, Dept Oral & Maxillofacial Surg, Ulm, Germany