Radiography (x-rays) is used in dentistry in order to show or confirm things to the dentist which can’t necessarily be seen or known with just clinical examination of a patient.
Generally radiographs are taken of a patient to show;
- Caries and the extent of them
- The state of existing restorations
- Bone levels e.g. prior to implant placement or to monitor bone loss due to periodontal disease
- The presence of unerupted or impacted teeth, retained roots and their position
- Development of children’s teeth
- The presence of abscesses, cysts or other diseases which can affect the jaws
- Size and number of roots of a tooth as well as the shape of roots e.g. prior to an extraction
- To monitor the progression of/existence of root fillings
- To view possible fractures and whether the pulp of a tooth is affected e.g. after trauma
- Sub-gingival calculus and true periodontal pockets
The results of the image produced allow the dentist to decide on appropriate treatment for the patient concerned.
Of course, only a person who is qualified in dental radiography is allowed to take radiographs of patients. Dentists, therapists and hygienists all learn about radiography as part of the course they take to qualify in their particular field; however other dental team members such as dental nurses, receptionists and technicians, must gain an extra qualification where they must complete a specific course and examination in dental radiography in order to be allowed to take dental radiographs.
To gain this extra qualification it is essential that the participant understands about types of radiographs, the production of a radiographic image, image processing, radiograph quality, correct positioning of equipment and patient, x-ray equipment and how it works, recommended doses of radiation, radiation safety and risks involved, associated laws and regulations, and of course the anatomy of the skull, among other things.
Generally the radiation dose that patients receive from most dental radiographs is reasonably small compared to the dose received for example, when having an x-ray taken of a fractured leg or when having a chest x-ray taken. The dose will vary depending on the specific type of radiograph taken the equipment used, and the size/age of the patient, but still the dose is reasonably low. However it is important to remember that all radiation doses are potentially dangerous.
For a radiograph to be produced there must be an image receptor – e.g. film or digital sensor, equipment which will produce x-ray photons – an x-ray beam, where settings can be adjusted according to patient, type of radiograph taken, and type of equipment used, there must also be equipment to process the image. Each of these items must be compatible with one another, for example using a digital sensor and a manual processor instead of appropriate software to produce an image, would mean that the image taken would not be possible to view.
The decision to take a dental radiograph is the responsibility of the dentist; they must decide whether they consider the benefit of the radiograph being taken to outweigh the risk involved. It is also the responsibility of the dentist to decipher the result of the image produced – radiographs show a 2D image of 3D object. Specific types of dental radiograph produce a specific view of teeth and/or jaws which allows the dentist to see the area of concern; therefore it is also the responsibility of the dentist to choose the type of radiograph required. Radiographs may not be taken without the consent of the patient concerned; it is their right to refuse if they choose to do so.