[1] Natl Hosp Org, Kyoto Med Ctr, Dept Oral & Maxillofacial Surg, Kyoto, Japan
[2] Otsu Red Cross Hosp, Dept Otolaryngol Head & Neck Surg, Otsu, Shiga, Japan
[3] Natl Hosp Org, Clin Res Inst, Kyoto Med Ctr, Div Clin Res Planning & Management, Kyoto, Japan
[4] Natl Hosp Org, Kyoto Med Ctr, Dept Pharm, Kyoto, Japan
[5] Natl Hosp Org, Kyoto Med Ctr, Clin Res Inst, Div Prevent Med, Kyoto, Japan
[6] Natl Hosp Org, Kyoto Med Ctr, Dept Oral & Maxillofacial Surg, 1-1,Fukakusa Mukathata,Fushimi Ku, Kyoto, Japan