First up let me re-iterate that X-rays are utterly vital to successful diagnosis and treatment. Keep that in mind when reading this section. Thinking of avoiding X-rays altogether? I urge you to think twice; the effect on your body of an undiagnosed infection would certainly be more harmful that having a couple of small X-rays at the dentist. However, we must do everything we can to minimise our exposure and make sure that there is always a good reason for taking the X-ray.
X-rays are a controlled form of ionizing radiation. This radiation is dangerous and can cause significant effects on the body. In cancer patients, ionizing radiation is used to try and control the malignant cells; this causes swelling, redness, inflammation and burning of the skin straight after treatment. Additional side effects of hair loss, dry mouth, dry eyes and infertility can occur later.
Fortunately in dentistry and medicine, the doses given are tiny in comparison, and far below that needed to cause such effects. However, unnecessary X-rays should always be avoided. Screening X-rays to assess for dental decay are necessary but how often you need them should be related to your caries risk and the likelihood of finding problems. Before you begin panicking, it is important to understand that every one of us is exposed to background ionizing radiation everyday anyway from our environment as we walk around doing day to day things.
An estimation of this environmental dose would be 2-4mSV per year (depending where you live), which is quite significant when compared to an intra-oral dental X-ray where the dose is only 0.002-0.016mSV.
For a table comparing the levels of radiation of dental X-rays to various other sources see the American Dental Association website
The dentist will keep your dose ‘ALARA’- as low as reasonably possible. You can help reduce the number of X-rays that you have taken in the following ways:
- Take your X-rays with you if possible to your new dentist if you move area, or have the old practice make copies.
- Take your X-rays with you, if you are referred for specialist treatment to save identical duplicates being taken.
- If you have just had X-rays let the dentist know. It may be a different view is needed or too much time has passed and another one is necessary, but it may not!
There are strict rules for dentists and their surgeries regarding X-rays to reduce exposure as much as possible to patients, staff and themselves. Dentists must follow these by law.
Current government guidelines are also in place for taking X-rays and should be followed; the importance of X-rays should not be underestimated but be balanced with the risks of ionizing radiation.
X-rays should be avoided unless absolutely necessary during pregnancy. The developing foetus is particularly sensitive in the period 2-9 weeks after conception when the vital organs are being formed. Thus routine X-rays should be delayed until after the birth. The foetus is however also at risk from untreated dental infections and so dental treatment including an X-ray may be needed to maintain the health of the mother and child.
Wearing a lead apron, used to be a standard X-ray safety precaution for patients, but with the development of more focused beams, holders, faster films and digital X-ray technology this is no longer as routinely done. Questions have been raised over whether the apron has any benefit.. and in fact someone say it may even be detrimental, preventing the scatter of radiation after it has hit the film or screen from exiting the body.
Doses of radiation can now be reduced even further by digital radiography and more and more practices are starting to use this.