1. Department of Anatomic Pathology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
2. Department of Diagnostic Pathology, Hashimoto Municipal Hospital, Hashimoto, Japan
3. Department of Oral and Maxillofacial Surgery, Hashimoto Municipal Hospital, Hashimoto, Japan
4. Department of Oral and Maxillofacial Surgery, Wakayama Medical University, Wakayama, Japan