[1] Okayama Univ, Grad Sch Med & Dent, Dept Orthodont, Okayama 7008525, Japan
[2] Univ Tokushima, Grad Sch, Inst Hlth Biosci, Dept Orthodont & Dentofacial Orthoped, Tokushima 770, Japan
[3] Tohoku Univ, Grad Sch Dent, Div Orthodont & Dentofacial Orthoped, Sendai, Miyagi 980, Japan