[1] Hiroshima Univ Hosp, Dept Oral & Maxillofacial Radiol, Minami Ku, Hiroshima 7348553, Japan
[2] Hiroshima Univ, Grad Sch Biomed Sci, Div Med Intelligence & Informat, Dept Oral & Maxillofacial Radiol, Hiroshima 730, Japan
[3] Hiroshima Univ, Grad Sch Biomed Sci, Div Clin Med Sci, Dept Obstet & Gynecol, Hiroshima 730, Japan
[4] Univ Washington, Sch Dent, Dept Orthodont, Seattle, WA 98195 USA