1. Division of Orthodontics, Department of Stomatology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan
2. Division of Oral Maxillofacial Surgery, Department of Stomatology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan
3. Department of Mechanical Engineering, College of Engineering, National Cheng Kung University, Tainan 704, Taiwan