Broadly, the code reflects common sense. This is just my interpretation. It’s not advice.
Some radiologists say that there is no such thing as a routine radiograph. They are at least in general dentistry for the purposes of an examination, to enable a procedure such as endodontics to be performed safely, or to diagnose or rule out the cause of symptoms and signs of pathology.
Radiographs should never be taken without an assessment of the patient. And radiography is appropriate including regular OPGs and BWs as a matter of course for most patients bearing in mind their reported dental and radiographic history.
No one is going to set hard and fast rules for each circumstance. It is an expectation that dental practitioners will only record radiographs when the diagnostic benefit exceeds the possible harm of the radiation.
Recording a CT as a scan for a child would rarely be appropriate. Recording BW radiographs every two year forr some other frequency may well be appropriate in some patients at risk.
Optimisation of protection is maximising the benefit-risk ratio of a medical exposure for that patient.
Radiation exposure must be minimised yet still sufficient to fulfil the clinical objective of the procedure, with account taken of relevant norms of acceptable image quality or therapeutic efficacy. Special attention is required for exposures of paediatric patients, for individuals undergoing health screening, for volunteers in medical research and where a fetus or breastfed infant may receive an incidental exposure.
This is self explanatory I believe. Better techniques mean less repeated unecessary exposures.
Dentists need to have a reason to suggest radiography and they need to assess that risk and explain it to the patient. A simple poster can be used showing the dose from say a PA and OPG and a CBCT compared to background radiation for example.
Diagnostic reference levels (DRLs), which give an indication of levels of doses to patients for common procedures, are one method that can be used as an optimisation tool in medical imaging. Their purpose is to raise awareness of patient doses and prompt medical radiation facilities administering doses greater than the reference levels to review procedures and revise or justify as appropriate.
See for example https://www.arpansa.gov.au/research-and-expertise/surveys/national-diagnostic-reference-level-service/current-australian-drls/mdct
Dentists should be aware of the DRLs and express the relevance of this even for intra oral radiographs and OPGS in my view to their patients.
See also Cameron Storm, Rikki Nezich. Establishment of a diagnostic reference level for dental intraoral bitewing X-rays in Western Australia, 20 January 2023, PREPRINT (Version 1) available at Research Square [https://doi.org/10.21203/rs.3.rs-2486760/v1]
As to justification, the 2018 code says
The principle of justification applies at three levels to the use of radiation in medicine.
At the first level, the use of radiation in medicine is accepted as doing more good than harm to patients.
At the second level, a specified procedure and objective is defined and justified (e.g. chest radiographs for patients showing relevant symptoms, or a group of individuals at risk of a condition that can be detected and treated). The aim of this generic justification is to judge whether the radiological procedure will usually improve diagnosis or treatment or will provide necessary information about the medical condition of the exposed individuals.
At the third level, the particular application must be judged to do more good than harm to a specific patient.
All individual medical exposures must be justified in advance, taking into account the specific objectives of the exposure and the characteristics of the medical condition of the individual involved.
Brad Wright January 20-25
