1. Division of Research and Treatment for Oral and Maxillofacial Congenital Anomalies, School of Dentistry, Aichi Gakuin University, Nagoya, Japan.
2. Department of Oral Anatomy, Aichi Gakuin University School of Dentistry, Nagoya, Japan.
3. Department of Oral and Maxillofacial Radiology, Nihon University School of Dentistry, Tokyo, Japan.