The decision to order diagnostic imaging as part of the evaluation of an orofacial complaint should be based on the principle of selection criteria. Selection criteria are those historical and/or clinical findings that suggest a need for imaging to provide additional information so that a correct diagnosis and an appropriate management plan can be determined. The use of selection criteria requires the clinician to obtain a history, perform a clinical examination, and then determine both the type of additional information required (if any) and the best technique for obtaining this information. The emphasis is on the acquisition of new information that affects the outcome, not just the routine application of a diagnostic modality.
There are many reasons for requesting imaging information, including the determination of the nature of a condition, the confirmation of a clinical diagnosis, the evaluation of the extent of a lesion, and the monitoring of the progression or regression of a lesion over time. Each of these may require a different imaging strategy.
Over the years, there have been some attempts to offer guidance to the clinician in the selection of the most appropriate imaging protocol. In 1986, the Food and Drug Administration convened a panel of experts to develop guidelines for selecting appropriate radiologic examinations for new and recall dental patients, both those who present for routine examination without complaints and those with specific signs or symptoms of disease.
These guidelines have been approved by the American Dental Association and all dental specialty organizations. A convenient chart of these recommendations can be obtained from Eastman Kodak Company, Rochester, New York (pamphlet No. N-80A).
Guidance for imaging of the temporomandibular joint (TMJ)
and dental implant preoperative site assessment
has been developed in the form of position papers published by the American Academy of Oral and Maxillofacial Radiology. That group has also produced a document describing parameters of care for a variety of imaging tasks.
Whether or not there are published guidelines, it is incumbent upon the individual clinician to use diagnostic imaging wisely. This means determining specifically what information is needed, deciding whether imaging is the best way to obtain this information, and (if so) selecting the most appropriate technique, after considering the information needed, the radiation dose and cost, the availability of the technique, and the expertise needed to interpret the study.