26.1

An extraoral image is an image that is placed outside the mouth during x-ray exposure. It is used to image large areas of the skull or jaws, and various projections are used in extraoral imagining.

The purpose and use of extraoral imaging include several important aspects. It is used to evaluate large areas of the skull or jaws and to assess growth and development. Additionally, it helps evaluate impacted teeth and detect diseases, lesions, and various conditions of the jaws. Extraoral imaging is also employed to examine large lesions’ extent and evaluate trauma. Furthermore, it is utilized to assess the temporomandibular joint area. However, it is important to note that extraoral imaging is not used to detect caries, periodontal disease, or periapical disease.

Equipment

Some important things to remember are scatter radiation, which is x-rays that bounce off bones and teeth, and contrast, which is the gradation between dark and light areas on an image.

Diagnostic Extraoral Image

A diagnostic extraoral image must demonstrate accurate anatomic features and proper density and contrast. Anatomic features vary depending on the extraoral projection, and proper density and contrast result from the use of correct exposure factors as recommended by the x-ray unit manufacturer.

Step-by-Step Procedures

Step-by-step procedures for the exposure of an extraoral projection include equipment preparation, patient preparation, and patient positioning. Infection control procedures must be completed before exposing an extraoral receptor. If an extraoral unit with cephalostat is used, the ear rods must be wiped with disinfectant between patients.