*Kentaro Igarashi1, Koji Iizuka1, Hikaru Kuriyagawa1, Moe Sakurai1, Ayu Fujii1, Arisa Yamazaki1, Asako Suzuki1, Toshikazu Miura2, Shizuka Tarukawa2, Masayasu Ito1, Yasuhiko Kawai1
(1. Removable Prosthodontics and Geriatric Oral Health, Nihon University School of Dentistry at Matsudo, 2. Removable Prosthodontics, Nihon University Graduate School of Dentistry at Matsudo)