The following is copy written by the American Veterinary Dental College:
Dental Radiographs (X-rays) in Veterinary Patients
Dental radiographs are one of the most important diagnostic tools available to a veterinary dentist. They allow the internal anatomy of the teeth, the roots and the bone that surrounds the roots to be examined.
Intra-oral radiographs are made using small radiographic films or digital sensors placed inside the patient's mouth, and provide superior quality for examination of individual teeth or sections of the jaws compared with standard-sized veterinary radiographs. Because veterinary patients will not cooperate when a radiograph or sensor is placed in the mouth, taking dental radiographs requires that the patient is anesthetized or sedated.
Your veterinarian or veterinary dental specialist will make a recommendation whether or not to take radiographs of all the teeth ("full-mouth radiographs"), based on the reason for presentation of the patient and the results of initial visual examination of the mouth. It is common for a patient referred for one specific problem to have additional oral problems - these may only become apparent if full-mouth radiographs are made. Full-mouth radiographs also establish a base-line for future comparison.
The radiation risk to the patient from taking dental radiographs is minimal. AVDC veterinary dental specialists make use of digital imaging systems when possible,
which significantly reduces the radiation exposure for the patient and veterinary staff present.
AVDC veterinary dental specialists are trained in interpreting dental radiographs and digital images, and are willing to review dental radiographs on request from general veterinary practitioners.