1. Oral and Maxillofacial Radiology; Tokyo Medical and Dental University, Tokyo, Japan.
2. Yoshida Dental Mfg. Co. Ltd; Diagnostic Imaging Division, Tokyo, Japan.
3. Oral and Maxillofacial Radiology; The University of Tokushima Graduate School
4. National Center for Geriatrics and Gerontology, Aichi, Japan.