Have you ever wondered, “Do I really need this X-ray?” It’s a reasonable question.
Dental X-rays do involve ionising radiation, so they should never be taken “just because”. The reassuring part is that modern dental imaging uses low doses, and Australian guidance is clear that any exposure must be justified and kept as low as necessary for the clinical purpose.
This blog post breaks down how dental X-rays work, the different types available, how radiation is managed, and how often imaging is typically recommended based on individual risk rather than a fixed schedule.
What Are Dental X-Rays?
Dental X-rays are images created using a small amount of ionising radiation. They allow dentists to detect issues that are not easily visible during a clinical examination, such as problems between teeth, beneath existing fillings, or within the supporting bone.
According to Australian Radiation Protection and Nuclear Safety Agency, this type of imaging plays an important role in identifying conditions early, often before symptoms appear.
The Main Types of Dental X-Rays
Different types of X-rays are used depending on what needs to be assessed.
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Bitewing X-rays are commonly used to detect decay between teeth and assess bone levels.
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Periapical X-rays show the entire tooth, including the root and surrounding bone, and are often used when investigating pain, infection, or cracks.
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Panoramic (OPG) X-rays provide a broader view of the jaws and are useful for assessing wisdom teeth, development, and general screening where appropriate.
Lateral cephalometric X-rays are typically used in orthodontics to assess jaw relationships and growth patterns.
What Is CBCT and When Is It Used?
Cone Beam CT (CBCT) is a three-dimensional imaging technique that provides detailed views of teeth, bone, and surrounding structures.
It can be helpful in more complex situations, such as planning implants, assessing impacted teeth, or evaluating anatomy before surgical procedures. However, international guidance makes it clear that CBCT should only be used when it is justified for the individual patient and when it provides additional information that will influence treatment decisions.
A small field CBCT focuses on a limited area, such as a single tooth or region, and is generally preferred when appropriate, as it reduces radiation exposure.
A large field CBCT captures a broader area and requires careful justification due to the higher radiation dose.
Guidelines from SEDENTEXCT emphasise using the smallest effective scan area and avoiding routine or repeated use without reassessing the need.
Why Dentists Recommend X-Rays
When clinically justified, dental X-rays can help identify issues early and guide treatment decisions. These may include decay between teeth, infections around roots, bone loss related to gum disease, and the position of impacted teeth such as wisdom teeth.
They are also important for planning more complex procedures, including implants, orthodontics, and surgical treatments.
Australian standards require that each exposure is justified and optimised, meaning the benefit of the information gained should outweigh the minimal radiation involved.
How Much Radiation Is Involved?
It can help to compare dental X-rays to everyday sources of radiation.
According to ARPANSA, the average person is exposed to around 5 microsieverts (µSv) of background radiation each day. A domestic flight, such as Darwin to Perth, exposes you to approximately 16 µSv, while a long-haul flight from London to Melbourne is around 42 µSv.
Most standard dental X-rays are 10 µSv or less. CBCT scans can be higher but typically remain under 80 µSv depending on the size and settings of the scan.
These comparisons show that while dental imaging does involve radiation, the levels used in modern dentistry are generally low and carefully controlled.
Do You Need a Lead Apron?
In many cases, lead aprons are no longer routinely required for dental X-rays. Current guidance from ARPANSA reflects that modern equipment and techniques already minimise exposure effectively.
What About X-Rays During Pregnancy?
Current Australian guidance indicates that standard dental X-rays, including intra-oral, panoramic, and cephalometric imaging, can be undertaken during pregnancy when necessary.
Best practice includes minimising unnecessary exposure, using appropriate beam limitation, and avoiding abdominal exposure. CBCT scans are generally postponed until after pregnancy where possible. If imaging is required, additional precautions may be considered, and professional advice may be sought.
How Radiation Is Kept Low (ALARA in Practice)
The principle guiding dental imaging is ALARA: As Low As Reasonably Achievable. This means using the lowest radiation dose that still provides a clear and useful image.
In practice, this involves only taking X-rays when they are clinically justified, using techniques that reduce the need for repeat images, and limiting the use of more complex imaging such as CBCT to situations where it adds meaningful value to treatment planning.
Are Dental X-Rays the Same as Phone Radiation?
Dental X-rays and mobile phone radiation are not the same.
Dental imaging uses ionising radiation, while mobile phones and Wi-Fi use non-ionising radiofrequency energy. According to the World Health Organization, no established health effects are expected from typical exposure to radiofrequency energy from wireless networks, although research into higher exposures continues.
How Often Do You Actually Need Dental X-Rays?
There is no single schedule that suits everyone. The timing of dental X-rays depends on individual factors such as decay risk, dental history, gum health, and whether imaging is likely to influence treatment decisions.
International guidance from organisations such as the American Dental Association and U.S. Food and Drug Administration suggests that:
- Adults at low risk of decay may only require bitewing X-rays every 24 to 36 months
- Higher-risk adults may benefit from imaging every 6 to 18 months
- Children and adolescents may require more frequent monitoring depending on their risk level
UK guidance from Faculty of General Dental Practice also reinforces that routine imaging based purely on time intervals is not appropriate. Instead, decisions should be based on individual risk and reassessed over time.
For gum disease, the type and frequency of imaging are guided by clinical findings rather than a fixed schedule.
Structured systems such as ICDAS and ICCMS can support risk-based decision-making, although imaging still needs to be individually justified.
The Bottom Line
Dental X-rays are not something to avoid entirely, but they are something to use thoughtfully.
When used appropriately, they can help detect problems earlier, support better planning, and reduce the likelihood of more complex treatment later on. You are always entitled to ask what the X-ray is for and how it will influence your care.
Understanding the purpose behind imaging can help you feel more confident in your decisions and more informed about your oral health.
Sources & Further Reading
ARPANSA/ADA Dental Imaging brochure (PDF + infographic):
https://www.arpansa.gov.au/sites/default/files/dental_imaging_brochure_final.pdf
ARPANSA dental imaging page (infographic online):
https://www.arpansa.gov.au/understanding-radiation/sources-radiation/more-radiation-sources/dental-imaging
ARPANSA RPS C-7 (2025): Code for Radiation Protection in Dental Exposure (PDF):
https://www.arpansa.gov.au/sites/default/files/documents/2025-02/Radiation%20Protection%20Series%20C-7%20-%20Code%20for%20Radiation%20Protection%20in%20Dental%20Exposure.pdf
ADA/FDA: Dental Radiographic Examinations – Recommendations for patient selection (PDF):
https://www.fda.gov/media/84818/download
FGDP(UK) Selection Criteria for Dental Radiography (updated 2018) (PDF):
https://cgdent.uk/wp-content/uploads/securepdfs/FGDP-SCDR-ALL-Web.pdf
SEDENTEXCT Radiation Protection 172 – CBCT evidence-based guidelines (PDF):
https://sedentexct.eu/files/radiation_protection_172.pdf
WHO – Wireless / RF fields:
https://www.who.int/teams/environment-climate-change-and-health/radiation-and-health/non-ionizing/wireless
ICCMS Guide (linked to ICDAS):
https://www.iccms-web.com/uploads/asset/59284654c0a6f822230100.pdf