Radiation protection in dental X-ray
ALARA, justification, and who is permitted to expose
X-ray radiation is ionizing and may only be used if it benefits the patient. Therefore the area is legally regulated, and the clinic must follow the authorities' requirements. As an assistant you must understand the principles behind, know your own role and know when to ask — not act on your own.
§The three basic principles of radiation protection
All use of ionizing radiation in the healthcare system is based on three principles that you should be able to.
| Principle | Meaning | In practice at the clinic |
|---|---|---|
| Justification | Admission should benefit more than radiation risks damaging | Only photographs that the dentist professionally needs are taken — not routinely |
| Optimization (ALARA) | Dose kept as low as reasonably achievable | Correct technique so recording does not need to be repeated; no more images than necessary |
| Dose limits | Personnel dose is kept below set limits | Distance, shielding and any personal dosimetry according to the clinic's arrangement |
§ALARA – as low as reasonably achievable
ALARA (As Low As Reasonably Achievable) means always aiming for the lowest possible dose that still provides a useful image. The most important practical consequence is to avoid retakes: a re-exposure due to faulty technique doubles the patient's dose. Therefore, good technique and calm patient guidance are also radiation protection.
§Distance and shielding
Radiation protection for staff is based on distance and shielding: good distance is maintained from the radiation field during exposure and the clinic's shielding is used. The clinic has fixed routines for where to stand and how the room is arranged so no one stands unnecessarily close when exposing.
§Special considerations
Certain situations require extra consideration e.g. pregnancy. The clinic's guidelines describe how such considerations are handled. Be open and ask the patient where the guidelines suggest it and follow the clinic's practice rather than improvising.
§The assistant's role
You often prepare for the scan, help the patient get comfortable, and link the image to the journal. Calm and clear guidance — hold completely still, bite here — gives a usable image on the first try and thereby saves dose. This way you're an active part of radiation protection, not just a helping hand.