Radiation Safety

Dental radiographic examinations require exposure to very low levels of radiation, which makes the risk of potentially harmful effects extremely small.  Like any medical test, the beneficial information gained from the test should outweigh the risk of having the test performed.  Intraoral dental x-rays, extraoral panoramic x-rays and dental cone beam computerized tomography (CBCT) are very powerful tools and valuable imaging techniques that can provide important information about your care and treatment.

At Deschutes Endodontics we prescribe to the ALARA principle.  ALARA is an acronym for As Low As Reasonably Achievable.  This is a radiation safety principle for minimizing radiation exposure to patients by: determining the need for and type of radiographs to take; using “best practices” during imaging, including the application of quality control procedures; and, interpreting the images completely and accurately.  We incorporate the use of abdominal shielding (e.g., protective aprons) and thyroid collars (when feasible) on all patients, especially for children, women of childbearing age, and pregnant women.  We also use digital imaging sensors which are the fastest image receptor requiring the lowest dose of radiation for diagnostic x-rays.

We believe that it is important for patients to have as much information as possible to enable them to make educated decisions about their care.  To better understand your exposure we have listed the effective radiation dose from various dental and medical sources with a comparison to the normal background exposure to radiation in the United States.

Radiation Dose Comparison

Diagnostic Procedure / Source of Radiation Typical Effective Dose (mSv) Time Period for Equivalent Effective Dose from Natural Background Radiation
Average Background Radiation Exposure per year in the United States 3 mSv per year
Dental X-ray Procedures:
Intraoral Dental x-ray 0.005 mSv 0.6 days
Panoramic Dental x-ray 0.007 – 0.01 mSv 0.85 – 1.2 days
Cone Beam CT x-ray 0.008 – 0.025 1 – 3 days
Medical X-ray Procedures: 
Chest x-ray 0.02 mSv 2.4 days
Skull x-ray 0.1 mSv 12 days
Medical CT (head) 2 mSv 243 days
Medical CT (abdomen) 16 mSv 2.7 years
Mammography 0.4 mSv 48 days

The information in the table above are averages.  The amount of exposure from any procedure will vary depending on several factors.  For example, the exposure from dental intraoral radiographs can vary depending on the type of dental film used or if a digital sensor is used to obtain the image.  Switching from a D-speed film to a faster E-speed film can produce a 20-25% reduction in radiation exposure.  Switching from E-speed film to a digital sensor can produce a 40-60% reduction in radiation exposure.  At Valley Endodontics we use state of the art intraoral digital sensors to provide the highest quality images with the least amount of exposure for our patients.

Sources:

1.Average effective dose in millisieverts (mSv) as compiled by Fred A. Mettler, Jr., et al., “Effective Doses in Radiology and Diagnostic Nuclear Medicine:  A Catalog,” Radiology Vol. 248, No. 1, pp. 254-263, July 2008.
2. Radiation dosage reduction in general dental practice using digital intraoral radiographic systems, Department of Oral and Maxillofacial Radiology, Tokyo Dental College, Chiba, Japan
www.fda.gov/RadiationEmittingProducts/RadiationEmittingProductsandProcedures/MedicalImaging/MedicalX-Rays/ucm115329.htm
www.fda.gov/RadiationEmittingProducts/RadiationSafety/RadiationDoseReduction/ucm199994.htm