1. Department of Otolaryngology–Head and Neck Surgery, Kyung Hee University School of Medicine, Seoul, Korea
2. Department of Oral & Maxillofacial Surgery, School of Dentistry, Kyung Hee University, Seoul, Korea
3. Department of Otolaryngology, Samsung Changwon Hospital, Sungkyun-kwan University School of Medicine, Changwon, Korea