[Radiation Protection in Orthodontics: relevant data].

For the past 30 years X-Ray images have effected a veritable revolution in medical practice. Using them practitioners cannot only make reliable and precise diagnoses when they begin a course of treatment but also accurately follow the progress of therapy. Orthodontics is one of the specialties that has benefited from the innovations in medical radiography. At the same time we have learned more about the risks that the use of ionizing radiation entails and are, accordingly, basing our radiological practice on the ALARA principle ("As Low As Reasonably Achievable"). Even though this concept is embodied in much national and European legislation, practitioners will enhance their daily use of radiology by acquiring an understanding of the scientific basis for ALARA.