1. The Third Department of Fixed Prosthodontics, School of Dentistry, Aichi-Gakuin University: 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651, Japan
2. Department of Oral and Maxillofacial Surgery, School of Dentistry, Aichi-Gakuin University, Japan
3. Department of Oral and Maxillofacial Radiology, School of Dentistry, Aichi-Gakuin University, Japan
4. Medical Corporation, Taguchi Dental Clinic, Japan