1. Department of Prosthodontics, One-Stop Specialty Center, Seoul National University Dental Hospital, Seoul, South Korea.
2. Department of Conservative Dentistry, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea.
3. Department of Periodontics, One-Stop Specialty Center, Seoul National University Dental Hospital, Seoul, South Korea.
4. Department of Prosthodontics, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea.