1. Division of Oral and Maxillofacial Surgery, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8514, Japan
2. Department of Dentistry and Oral Surgery, Aizu Chuo Hospital, Aizu Wakamatsu 965-8611, Japan
3. Oral Pathology Section, Department of Surgical Pathology, Niigata University Hospital, Niigata 951-8520, Japan
4. Division of Oral Pathology, Niigata University Graduate School of Medical and Dental Sciences, 2-5274 Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan
5. Oral Implant Clinic, Niigata University Hospital, Niigata 951-8520, Japan
6. Division of Reconstructive Surgery for Oral and Maxillofacial Region, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8514, Japan