1. Department of Oral and Maxillofacial Surgery, School of Dentistry, Seoul National University, Seoul, Korea.
2. Department of Oral and Maxiilofacial Surgery, College of Dentistry, Gangneung-Wonju National University, Gangneung, Korea.
3. Department of Dental Anesthesiology, Dental Research Institute, School of Dentistry, Seoul National University, Seoul, Korea.