1. Department of Prosthodontics, College of Dentistry, Kyung Hee University, Seoul, Republic of Korea.
2. Department of Biomaterials and Prosthodontics, Kyung Hee University College of Dentistry, Kyung Hee University Dental Hospital at Gangdong, Seoul, Republic of Korea.
3. Department of Oral and Maxillofacial Surgery, Kyung Hee University College of Dentistry, Kyung Hee University Dental Hospital at Gangdong, Seoul, Republic of Korea.
4. Department of Periodontics, Kyung Hee University College of Dentistry, Kyung Hee University Dental Hospital at Gangdong, Seoul, Republic of Korea.