1. Division of Oral Surgery, National Hospital Organization Yonago Medical Center, Yonago 683-0006, Japan
2. Division of Oral and Maxillofacial Biopathological Surgery, Department of Sensory and Motor Organs, School of Medicine, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
3. Division of Oral Surgery, Matsue Red Cross Hospital, Matsue 690-8506, Japan