Extracts from the faculty of General Dental Practitioners (UK) and the Royal College of Surgeons of England good practice guidelines-

"Selection Criteria for Dental Radiography" 2004; (ISBN:0 9543451 1 8)

The new patient to the practice
"Research has shown that intra-oral (bitewing and periapical) radiography is superior to panoramic radiography for the diagnosis of common dental pathology (caries, periodontal and periapical pathology)……"(page 20, section 2.2.1)

The edentulous patient
"In the absence of any clinical signs or symptoms there is no justification for any radiographic examination unless implant treatment is planned. Where clinical examination identifies the possible presence of an abnormality, such as a possible retained root, then an intra-oral radiograph is the appropriate radiographic examination."(Page 20, section 2.2.2)

Trauma
"If there is clinical evidence of a bony fracture it is probably more appropriate for a dentist to refer the patient for a complete radiographic examination at the hospital where treatment will be performed……For simple dental trauma, intra-oral radiography will provide greater diagnostic detail (than panoramic)" (Page 22, section 2.2.5)

Temporomandibular joint (TMJ) problems
"A study of patients with symptoms and signs related to the TMJ region found that panoramic radiography provided little or no information that influenced diagnosis or patient management in the majority of cases examined. (Page 23, section 2.2.6)

Suggested selection criteria for panoramic radiography

Panoramic radiographs should only be taken in the presence of specific clinical signs and symptoms. There is no justification for review panoramic radiography at arbitrary time intervals.

All patients must have a clinical history taken prior to panoramic radiography. When radiographs are clinically indicated, intra-oral radiographs should be considered first because of better detail and lower radiation doses." (page 23, section 2.2.7)