Are Dental X-rays Safe?

We are often asked by our patients about the safety of dental x-rays.  Many people are concerned about the levels of radiation they are exposed to when diagnostic x-rays are taken.  Since exact measurements are difficult to obtain, this article will use averages and comparisons to help you understand what levels of radiation you are receiving with dental x-rays.

Risk

There is risk associated with any type of x-ray because it involves the use of radiation.  The level of risk varies among the different types of x-rays and is typically measured in a unit of effective dose called a milliSievert (mSv).  What most people worry about when they hear “radiation” is whether or not it can cause cancer.  According to the World Health Organization’s publication, Communicating radiation risks in paediatric imaging: Information to support healthcare discussions about benefit and risk, the risk of cancer incidence that is increased by various types of diagnostic x-rays is compared with a baseline lifetime cancer risk.  This publication is focused on the risk to children because: “Stochastic risks are of special concern in pediatric imaging since children are more vulnerable than adults to the development of certain cancer types, and have longer lifespans to develop long-term radiation-induced health effects.” Basically, kids are more susceptible than adults to cancer from radiation.  Their studies showed that the increase in cancer incidence for children aged 1-10 years from dental x-rays is negligible (<1 in 500,000).  That risk would be even lower in an adult.

The risk is also measured by comparing it to the naturally occurring radiation that all people are exposed to on a daily basis.  These measurements vary widely based on location (there is a black sand beach in Brazil with the highest level of natural radiation on earth), so a worldwide average and national US average are shown in a chart on background radiation from Wikipedia.

A set of four bitewing x-rays, which is typically taken once per year, has an average effective dose of 0.005mSv.  The average amount of radiation someone in the US receives from cosmic radiation is 0.33mSv, more than 66 times that of your yearly dental x-rays.  The graph below shows other levels of natural background radiation experienced annually.

Click to enlarge

Benefit

The benefit of these x-rays is the early detection of multiple types of oral disease, including cavities, gum and bone infections, and oral cancer.  As with any disease, the earlier it is detected, the less invasive treatment can be and the better the long-term prognosis.  The risk of these diseases going undetected is the progression of disease, spread of infection, loss of teeth, loss of bone in the jaws, and in severe cases even death.

Risk vs. Benefit

Due to the prevalence of oral diseases and the risks associated with those diseases, it is the opinion of our practice, as well as that of the American Dental Association, that the benefits of early detection with diagnostic x-ray imaging outweigh the risks associated with the x-rays.  Patients are far more likely to experience the consequences of undetected dental and oral diseases than they are to experience an increased cancer incidence due to dental x-rays.  Because each patient has different risk factors, the number of x-rays and the frequency at which they are taken can vary widely.  For example, a patient with a high risk for cavities needs dental x-rays on a more frequent basis than a patient who has a low risk.  A patient with extensive dental work needs more dental x-rays than a patient with no existing dental work.

X-rays and Pregnancy

The American College of Obstetricians and Gynecologists Committee on Health Care for Underserved Women reaffirmed its committee opinion in 2015: “Patients often need reassurance that prevention, diagnosis, and treatment of oral conditions, including dental X-rays (with shielding of the abdomen and thyroid) … [is] safe during pregnancy.”  Dr. Chowning typically postpones any dental x-rays during a patient’s pregnancy until after the baby is born unless the patient has a very high risk for dental disease, which could affect the patient’s overall health and that of the pregnancy.

Concerned about Radiation from Dental X-rays?

The number and type of dental x-rays taken on every patient is customized for his or her specific needs.  Call our office at 940-382-1750 to set up a consultation with Dr. Chowning.