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Dental X-Ray Radiation Comparator

Pick the dental X-rays you had or were offered, from bitewings to a 3D CBCT scan. See the dose range in microsieverts, compared with natural background radiation, a coast-to-coast flight and a chest X-ray.

Example shown: one checkup set of 4 bitewings. Add the X-rays you had or were offered.
Which X-rays, and how many?
Collimator (the opening on the X-ray tube)

Only changes bitewings and periapicals. A rectangular one cuts their dose by up to about five times. "Not sure" shows both.

Image receptor (for bitewings and periapicals)

D-speed is the oldest, slowest film. If you're not sure, ask your dental office.

Who is having the X-rays?

Changes the 3D (CBCT) numbers, which were measured separately for children.

Estimated effective dose

Adult

2–24 µSv

For 1 set of 4 bitewings.

Natural background6 hours to 2.9 days
Coast-to-coast flights6%–70% of one flight
Chest X-rays2%–24% of one chest X-ray
Microsieverts (µSv). Your range compared with 1 day of natural background radiation in the US, a one-way coast-to-coast flight and a chest X-ray.

Dose by X-ray type

Effective dose for one of each, in microsieverts (µSv), for adults. Bitewings and periapicals are shown with a rectangular collimator and digital or F-speed film; the next column shows them with a round one. 1,000 µSv = 1 mSv.

X-rayDose (µSv)Round collimator (µSv)Where the numbers come from
Bitewings, 2 images1–2.54.9–12Half of the 4-bitewing range (2 images instead of 4).
Bitewings, set of 42–59.8–24Health Physics Society: 2–3 µSv. Ludlow 2008 (2007 ICRP method): 5.0 µSv. RadiologyInfo: 5 µSv for a dental X-ray.
Periapical, 1 image1.3–1.96.1–9.5Ludlow 2008 per image: 5.0 µSv ÷ 4 bitewings and 34.9 µSv ÷ 18 full-mouth images. RP172 puts one intraoral image under 1.5 µSv.
Full-mouth series (about 18 images)10–3549–171Health Physics Society: 10–15 µSv. Ludlow 2008: 34.9 µSv for 18 images.
Panoramic2.7–25n/aRP172: 2.7–24.3 µSv (Ludlow 2008 measured 14.2 and 24.3 µSv on two machines). Health Physics Society: 6–11 µSv. RadiologyInfo: 25 µSv.
Cephalometric (side of head)5.6–11n/aLudlow 2008: 5.6 µSv (lateral view). RP172: under 6 µSv. Health Physics Society: 6–11 µSv.
CBCT 3D scan, small field61–84
widest 5–674		n/aTypical: 61 µSv (RP172 median for small and medium scans) to 84 µSv (Ludlow 2015 mean for small scans). Widest: 5–652 µSv (Ludlow 2015) and 11–674 µSv (RP172). Children: 43 µSv (RP172 median, 10-year-old) to 103 µSv (Ludlow 2015 mean); widest 7–521 µSv.
CBCT 3D scan, medium field61–177
widest 9–674		n/aTypical: 61 µSv (RP172 median for small and medium scans) to 177 µSv (Ludlow 2015 mean for medium scans). Widest: 9–560 µSv (Ludlow 2015) and 11–674 µSv (RP172). Children: 43 µSv (RP172 median, 10-year-old) to 175 µSv (Ludlow 2015 mean, large and medium); widest 13–769 µSv.
CBCT 3D scan, large field87–212
widest 30–1,073		n/aTypical: 87 µSv (RP172 median for large scans) to 212 µSv (Ludlow 2015 mean). Widest: 30–1073 µSv (RP172) and 46–1073 µSv (Ludlow 2015). Children: 175 µSv (Ludlow 2015 mean, large and medium) to 186 µSv (RP172 median, 10-year-old); widest 13–769 µSv.

The everyday comparisons

ComparisonDose (µSv)Source
1 day of natural background radiation (US average)about 8.5 µSv3.1 mSv a year from natural sources (NCRP Report 160, as quoted by the ADA and the Health Physics Society), divided by 365
One-way coast-to-coast US flightabout 35 µSvCDC. RadiologyInfo gives about 30 µSv for a round trip.
Chest X-rayabout 100 µSvRadiologyInfo. The Health Physics Society lists 170 µSv for front and side views.

How much radiation is a dental X-ray?

Regular dental X-rays give a very small dose. A checkup set of 4 bitewings is about 2–5 microsieverts (µSv) with a rectangular collimator and digital or F-speed film. That's about 6 to 14 hours of the natural background radiation everyone in the US gets from soil, radon and space. A panoramic X-ray is about 3–25 µSv.

3D cone-beam CT (CBCT) scans are different. A typical scan is about 60–210 µSv, or about 1 to 4 weeks of background radiation, and some machines and settings go above 1,000 µSv. That's why dentists use CBCT only when regular X-rays can't answer the question.

How this tool works

The tool adds up the effective dose of each X-ray you pick. Effective dose takes into account how sensitive each organ is, so doses from different kinds of X-rays can be compared. It's measured in microsieverts: 1,000 µSv = 1 millisievert (mSv).

  1. Dose for each X-ray. We use published ranges, and where sources differ we keep the whole range. For example, the Health Physics Society lists 2–3 µSv for 4 bitewings and Ludlow and colleagues (2008) measured 5.0 µSv, so we show 2–5 µSv. The table under the tool lists every source.
  2. Your setup. Ranges for bitewings and periapicals assume a rectangular collimator and a digital phosphor plate or F-speed film. In Ludlow's measurements, a round collimator raised a full-mouth series from 34.9 to 170.7 µSv (about 4.9 times), and slower D-speed film raised it again to 388 µSv (about 2.3 times). The tool applies those ratios. "Not sure" shows the range from rectangular to round.
  3. 3D scans. The main range runs between the median in the European RP172 guidelines and the mean in Ludlow's 2015 review. The widest published range is shown too. Children have their own CBCT numbers.
  4. Comparisons. Natural background radiation in the US is about 3.1 mSv a year (NCRP Report 160, quoted by the ADA and the Health Physics Society). That's about 8.5 µSv a day. A one-way coast-to-coast flight is about 35 µSv (CDC), and a chest X-ray is about 100 µSv (RadiologyInfo). The Health Physics Society lists 170 µSv for a chest X-ray with front and side views.

Honest limits: these are typical figures, not a measurement of your own dose. Machines, settings, head size and technique all change the real number. Doses worked out with the older 1990 method are lower: Ludlow found the 2007 method gave doses 32% to 422% higher. Some digital sensors may need less than our figures. The ADA/FDA guidance says digital imaging can cut the dose by 40% to 60%.

How often do you need dental X-rays?

There's no fixed schedule. The ADA says there is no "one size fits all" interval. Your dentist should examine you, look at your history and any earlier X-rays, and then decide. New ADA and AAOMR recommendations from 2026 update the 2012 ADA/FDA guidance and keep this approach. The 2012 guidance gave these ranges for checkup bitewings:

PatientCavities or higher riskNo cavities and not higher risk
Child (baby or mixed teeth)Every 6–12 months*Every 12–24 months*
TeenEvery 6–12 months*Every 18–36 months
AdultEvery 6–18 monthsEvery 24–36 months

*Only if the dentist can't see or probe between the back teeth.

Insurance limits are a different thing. Plans set how often they'll pay. The ADA notes that many plans pay for one full-mouth series in five years, and some count a panoramic plus bitewings as a full-mouth series. The Dental Insurance Calculator tracks these limits. Pediatric dentists (AAPD) point out that insurance coverage on its own is not a reason to take X-rays.

Dental X-rays during pregnancy

The ADA says dental X-rays are considered safe at any stage of pregnancy. It also says abdominal or thyroid shielding is no longer recommended. The Health Physics Society says there's no information suggesting any risk to an unborn baby from a mother's dental X-rays. It adds that the dose to the baby is tiny, with or without a lead apron.

Needed dental care can go ahead, too. The ADA notes that it and the American College of Obstetricians and Gynecologists agree that urgent treatment, such as an extraction or root canal, can be done safely during pregnancy. Tell your dentist you're pregnant so they can plan with you.

Dental X-rays for children

Children are more sensitive to radiation than adults. Image Gently estimates their risk from radiation at about 3 to 5 times an adult's. The AAPD says X-rays should be chosen for each child's own needs, not by age alone. Intraoral X-rays (bitewings and periapicals) are the standard. CBCT can help with problems like impacted or extra teeth, injuries or surgery planning, but it isn't a first test without a clinical reason.

Some panoramic machines can take "extraoral bitewings". The AAPD says these give about the same dose as a panoramic, which is 3 to 11 times more than regular bitewings. To follow your child's teeth without X-rays, try the Baby Teeth Tracker and the Adult Teeth Predictor.

Thyroid collars and lead aprons: what changed

Advice on shields has changed in the last few years:

  • 2012: The ADA/FDA guidance said thyroid collars should be used whenever possible, and that abdominal shielding may not be necessary.
  • 2023: The American Academy of Oral and Maxillofacial Radiology recommended stopping thyroid, gonadal and fetal shielding for all dental X-rays, including panoramic, cephalometric and CBCT.
  • 2024: An ADA expert panel said thyroid collars are no longer recommended for any dental imaging. Collars and aprons can block the X-ray beam, which can mean extra X-rays.
  • 2025: The AAPD agreed that routine shielding is no longer necessary for children.

Dentists must still follow state and local radiation rules, so you may still see aprons in some offices. If you have questions about shields, ask your dentist.

How to lower your dose

  • Rectangular collimator. It narrows the beam to the size of the sensor. The ADA/FDA guidance says it cuts the dose up to fivefold compared with a round one.
  • Fast receptors. F-speed film or digital sensors need less radiation than slower film. F-speed film cuts exposure by 20% to 50% compared with E-speed.
  • Only the X-rays you need. Guidance from the ADA, the FDA and the AAPD all say to pick X-rays for your own risk.
  • Share old X-rays. If you change dentists, ask for your records to be sent. The AAPD says earlier X-rays help decide whether new ones are needed.
  • Smallest 3D scan. If you need a CBCT, ask why and what field size will be used. A small field usually gives a lower dose than a large one.

To find the teeth named on your X-ray report, use the Tooth Number Chart.

Frequently asked questions

How much radiation is in a dental X-ray?
Very little for regular X-rays. A checkup set of 4 bitewings is about 2–5 µSv with a rectangular collimator and digital or F-speed film, roughly 6–14 hours of natural background radiation. A panoramic is about 3–25 µSv. 3D (CBCT) scans are much higher: typically about 60–210 µSv, and up to about 1,000 µSv on some machines.
How often should I get dental X-rays?
There's no fixed schedule. The ADA says there is no "one size fits all". Under the ADA/FDA guidance, adults with cavities or a higher risk may need checkup bitewings every 6–18 months, and adults with no cavities and no higher risk every 24–36 months. Your dentist decides after examining you.
Can I have dental X-rays while pregnant?
Yes. The ADA says dental X-rays are considered safe at any stage of pregnancy, and that abdominal or thyroid shielding is no longer recommended. The Health Physics Society says it knows of no information suggesting any risk to an unborn baby from dental X-rays. Tell your dentist you're pregnant so they can plan your care.
Why didn't my dentist use a lead apron or thyroid collar?
Current advice says they aren't needed. In 2023 the American Academy of Oral and Maxillofacial Radiology recommended stopping thyroid, gonadal and fetal shielding for dental X-rays. In 2024 the ADA said thyroid collars are no longer recommended for any dental imaging. Shields can block the X-ray beam and lead to retakes. Dentists must still follow their state's radiation rules, so practices vary.
Will my insurance pay for X-rays at every visit?
Usually not. Plans set frequency limits. The ADA notes that many plans pay for one full-mouth series in five years, and some count a panoramic plus bitewings as a full-mouth series. Check your plan, and use the Dental Insurance Calculator to estimate costs.
Is a dental CBCT scan the same as a hospital CT scan?
No. Dental CBCT usually gives a lower dose. The European RP172 guidelines list 280–1,410 µSv for a medical CT of both jaws, against typical (median) dental CBCT doses of 61 µSv for small and medium scans and 87 µSv for large ones. Some CBCT settings overlap with medical CT, so ask which field size will be used.

Sources

  1. American Dental Association. X-Rays/Radiographs (Oral Health Topics). topic last updated March 26, 2026. Accessed October 26, 2026.
  2. American Dental Association. Pregnancy (Oral Health Topics). last updated July 14, 2025. Accessed October 26, 2026.
  3. American Dental Association Council on Scientific Affairs and U.S. Food and Drug Administration. Dental Radiographic Examinations: Recommendations for Patient Selection and Limiting Radiation Exposure. revised 2012. Accessed October 26, 2026.
  4. Benavides E, Krecioch JR, Connolly RT, et al. Journal of the American Dental Association 2024;155(4):280-293.e4. Optimizing radiation safety in dentistry: Clinical recommendations and regulatory considerations. 2024. ADA expert panel report (doi:10.1016/j.adaj.2023.12.002), summarized on the ADA X-Rays/Radiographs page: thyroid collars are no longer recommended for any dental imaging. Accessed October 26, 2026.
  5. Benavides E, Krecioch JR, Allareddy T, et al. Journal of the American Dental Association 2026;157(1):20-35.e5. American Dental Association and American Academy of Oral and Maxillofacial Radiology patient selection for dental radiography and cone-beam computed tomography: Clinical recommendations. 2026. Updates the 2012 ADA/FDA recommendations (doi:10.1016/j.adaj.2025.10.013). Abstract checked through Europe PMC. Accessed October 26, 2026.
  6. Benavides E, Bhula A, Gohel A, et al. Journal of the American Dental Association 2023;154(9):826-835.e2. Patient shielding during dentomaxillofacial radiography: Recommendations from the American Academy of Oral and Maxillofacial Radiology. 2023. Recommends discontinuing gonadal, pelvic and fetal shielding, and not using thyroid shielding for intraoral, panoramic, cephalometric and CBCT imaging. Abstract checked through Europe PMC. Accessed October 26, 2026.
  7. American Academy of Pediatric Dentistry, Reference Manual of Pediatric Dentistry. Prescribing Dental Radiographs for Infants, Children, Adolescents, and Individuals with Special Health Care Needs. latest revision 2025. Accessed October 26, 2026.
  8. Ludlow JB, Davies-Ludlow LE, White SC. Journal of the American Dental Association 2008;139(9):1237-1243. Patient risk related to common dental radiographic examinations: the impact of 2007 International Commission on Radiological Protection recommendations regarding dose calculation. 2008. Abstract figures checked in the PubMed record (PMID 18762634). Accessed October 26, 2026.
  9. Ludlow JB, Timothy R, Walker C, et al. Dentomaxillofacial Radiology 2015;44(1):20140197. Effective dose of dental CBCT: a meta analysis of published data and additional data for nine CBCT units. 2015. Accessed October 26, 2026.
  10. European Commission, Radiation Protection No. 172 (SEDENTEXCT project); copy hosted by Image Gently. Cone Beam CT for Dental and Maxillofacial Radiology: Evidence-based Guidelines (Tables 2.3a–c). 2012. Accessed October 26, 2026.
  11. RadiologyInfo.org (American College of Radiology and Radiological Society of North America). Radiation Dose from X-Ray and CT Exams. reviewed April 15, 2025. Accessed October 26, 2026.
  12. Health Physics Society, Ask the Experts. Dental-Patient Issues. Accessed October 26, 2026.
  13. Health Physics Society fact sheet. Common Sources of Radiation. revised September 2020. US average 6.2 mSv a year, about 3.1 mSv from natural background (after NCRP Report 160, 2009). Accessed October 26, 2026.
  14. Centers for Disease Control and Prevention. Facts About Radiation from Air Travel. July 15, 2026. Accessed October 26, 2026.
  15. Image Gently (Alliance for Radiation Safety in Pediatric Imaging). What Parents Should Know about the Safety of Dental Radiology. 2017. Accessed October 26, 2026.
  16. American Dental Association, Council on Dental Benefit Programs. Responding to Claim Rejections. Accessed October 26, 2026.
  17. American College of Obstetricians and Gynecologists, Committee Opinion No. 569. Oral Health Care During Pregnancy and Through the Lifespan. 2013. Cited by the ADA Pregnancy page; the ACOG site blocks automated checks. Accessed October 26, 2026.

Last reviewed by the Dental Health Time editorial team, against the sources above. How we review.

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