[Imaging of temporo-mandibular disorders].

Dominated for years by standard films (tomographic mouth open and mouth closed X-rays, MRI) radiographs of the TMJ have progressively lost their usefulness to diagnosticians who have progressively increased their reliance on well codified clinical examinations, which suffice in a great majority of cases.The indications for and diagnostic worth of radiological studies and the impact they have on the management of TMJ disorders are today quite low especially when the high cost of procedures like MRI, computerized tomography, and CBCT is taken into account. In this article we discuss the various maladies that dentists might encounter and the situations in which radiological examinations are still indicated.

[Indications for radiography in orthodontics and dentofacial orthopedics].

The risks associated with the use of ionizing radiation are a constant concern not only for practitioners but also for legislators who have included this ethical rule in the Code of public safety. It proposes reduction of risks by insisting that all X-Rays be taken only when they accord with one of the fundamental principles of X-Ray protection: they must be justified by clear diagnostic need. In direct application of this principle the French government in 2006 published a guide for the management of radiological and dental and stomatological examinations.

[Measurement errors in 3D cephalometrics: about the buccal cranio-facial analysis].

The development of three-dimensional radiological techniques generating low levels of radiation, like computed tomography and positron emission tomography with cone beam, has made it possible for orthodontists to utilize three dimensional cephalometry for certain complex clinical cases instead of conventional two dimensional imagery. Nevertheless, these new techniques rely on the identification of the most dependable anatomic landmarks. Fifteen randomly selected orthodontists were asked to identify on a computed tomography film 33 points that were chosen for a buccal cranio-facial analysis because they have been traditionally recognized for their reproducibility.

[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.