Oral Health Topics
Radiation exposure associated with dentistry represents a minor contribution to the total exposure from all sources. The National Council on Radiation Protection and Measurements (NCRP) has estimated that the mean effective radiation dose from all sources in the United States is 6.2 millisieverts (mSv) per year, with about 3.1 mSv of this dose from natural sources and about 3.1 mSv from man-made sources. About half of the man-made radiation exposure is related to CT scanning.
Occupational exposure in dental settings is far lower than that in hospitals and medical offices. According to the NCRP, the total limit for occupational exposure is 50 mSv in one year. In addition, the lifetime occupational effective dose is limited to 10 mSv times the number of an individual’s age. The NCRP concludes that occupational exposure for dental personnel will not exceed these limits, excepting for problems associated with facility design, diagnostic equipment performance, or operating procedures. For pregnant dental personnel, the radiation exposure limit is 0.5 mSv per month.
 National Council on Radiation Protection and Measurements. Ionizing Radiation Exposure of the Population of the United States. 2009. NCRP Report No. 160.
Radiation Safety Requirements
State laws and regulations set specific requirements for the use of ionizing radiation (which includes X-rays). Contact the state radiation protection program to determine specific requirements for:
- Inspection and testing for the facility, X-ray machine, radiation monitoring equipment and radiograph processing equipment
- Permits or licensing
- Supervision of personnel
- Use of dosimetry badges
- Training or certification
- Dental office design and radiation shielding
- Record keeping
Radiographic training requirements for dental office personnel frequently differ from and are less rigorous than those of medical personnel who take X-ray. Training requirements for dental office personnel typically are found in state dental practice acts or dental board regulations.
Guide to Patient Selection and Limiting Radiation Exposure
The ADA, in collaboration with the FDA, developed recommendations for dental radiographic examinations to serve as an adjunct to the dentist’s professional judgment of how to best use diagnostic imaging. Radiographs can help the dental practitioner evaluate and definitively diagnose many oral diseases and conditions. However, the dentist must weigh the benefits of taking dental radiographs against the risk of exposing a patient to X-rays, the effects of which accumulate from multiple sources over time. The dentist, knowing the patient’s health history and vulnerability to oral disease, is in the best position to make this judgment. For this reason, the recommendations are intended to serve as a resource for the practitioner and are not intended to be standards of care, nor requirements or regulations.