1. Department of Periodontology; School of Dentistry; Kyung Hee University; Seoul Korea
2. Clinic for Fixed and Removable Prosthodontics and Dental Material Science; University of Zürich; Zürich Switzerland
3. Research Institute for Biological Functions; CHUBU University; Aichi Japan
4. Clinical Research Center; School of Medicine; Inha University; Incheon Korea
5. Department of Periodontology; School of Dentistry and Institute of Oral Bioscience; Chonbuk National University; Jeonju Korea
6. Research Institute of Clinical Medicine of Chonbuk National University-Biomedical Research Institute of Chonbuk National University Hospital; Jeonju Korea