1. Department of Oral and Maxillofacial Surgery, Sapporo Higashi Tokusyukai Hospital
2. Department of Dentistry and Oral Surgery, Azabu Triology Hospital
3. Department of Oral and Maxillofacial Surgery, Division of Oral Pathobiological Science, Graduate School of Dental Medicine, Hokkaido University
4. Department of Oral and Maxillofacial Surgery, Sapporo City General Hospital