1 Department of Oral and Maxillofacial Surgery, Kakogawa Central City Hospital, 439 Hon-machi, Kakogawa-cho, Kakogawa, 675-8611, Japan. eiwata@med.kobe-u.ac.jp.
2 Department of Oral and Maxillofacial Surgery, Kobe University Graduate School of Medicine, Kobe, Japan.
3 Department of Oral and Maxillofacial Surgery, Kakogawa Central City Hospital, 439 Hon-machi, Kakogawa-cho, Kakogawa, 675-8611, Japan.
4 Department of Oral and Maxillofacial Surgery, Hyogo Prefectural Awaji Medical Center, Awaji, Japan.