[1] Hokkaido Univ, Fac Med, Dept Plast & Reconstruct Surg, Kita 15 Nishi 7,Kita Ku, Sapporo, Hokkaido 0608638, Japan
[2] Hokkaido Univ, Grad Sch Med, Kita 15 Nishi 7,Kita Ku, Sapporo, Hokkaido 0608638, Japan
[3] Hokkaido Univ, Grad Sch Dent Med, Dept Oral Diag & Med, Kita 13,Nishi 7,Kita Ku, Sapporo, Hokkaido 0608586, Japan
[4] Asahikawa Med Univ, Grad Sch Med, Dept Plast & Reconstruct Surg, 2-1-1-1 Midorigaoka higashi, Asahikawa, Hokkaido 0788510, Japan