*Yoshiki Ishida1, Satoru Watanabe2, Daisuke Miura1, Akikazu Shinya1,3
(1. Department of Dental Materials Science, School of Life Dentistry at Tokyo, The Nippon Dental University, 2. 2Department of Crown and Bridge, School of Life Dentistry at Tokyo, The Nippon Dental University, 3. Department of Prosthetic Dentistry and Biomaterials Science, Institute of Dentistry, University of Turku)