1. Department of Dental Biomaterials and the Institute of Biomaterial and Implant, College of Dentistry, Wonkwang University, Iksan 54538, Republic of Korea
2. Department of Prosthodontology, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
3. Department of Oral and Maxillofacial Surgery, College of Dentistry, Wonkwang University, Iksan 54538, Republic of Korea