1. Department of Oral and Maxillofacial Pathology, School of Dentistry and Institute of Oral Biology; Kyung Hee University; Seoul Korea
2. Department of Biomaterials & Prosthodontics; School of Dentistry; Kyung Hee University; Gangdong Korea
3. Department of Periodontology, School of Dentistry; Kyung Hee University; Seoul Korea