1. Division of Reconstructive Surgery for Oral and Maxillofacial Region, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Niigata 951‑8514, Japan
2. Oral Pathology Section, Department of Surgical Pathology, Niigata University Hospital, Niigata, Niigata 951‑8520, Japan
3. Division of Oral Pathology, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Niigata 951‑8514, Japan
4. Division of Oral and Maxillofacial Surgery, Faculty of Dentistry and Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Niigata 951‑8514, Japan