1. Section Preventive Dentistry and Pediatric Dentistry, Department of Orthodontics, Jena University Hospital, 07743 Jena, Germany
2. Department of Orthodontics, Jena University Hospital, 07743 Jena, Germany
3. Section of Pediatric Radiology, Department of Radiology, Jena University Hospital, 07747 Jena, Germany
4. Radiation Protection, Centre for Health and Safety Management, Jena University Hospital, 07747 Jena, Germany