1. Kamishihoro Dental Clinic, E4-241, Kamishihoro-cho, Katogun, Hokkaido 080-1408, Japan
2. Department of Biochemistry and Molecular Biology, Graduate School of Dental Medicine, Hokkaido University, N13 W7, Kita-ku, Sapporo, Hokkaido 060-8586, Japan
3. Stomatognathic Function, Center for Advanced Oral Medicine, Hokkaido University Hospital, N13 W7, Kita-ku, Sapporo, Hokkaido 060-8586, Japan