Too Many Dental X-rays

The screening dental X-ray has been a pet peeve of mine for years. Although I know nothing about dentistry, the practice of screening X-rays without data to support it is anathema to me. At each of my dentist’s appointments, whether I get an X-ray depends mostly on how much energy I have on the given day: am I wide awake and energized enough to refuse, or do I just want to get the appointment over with and get to work?

Dr. Sheila Feit has done a nice job here of asking good questions and reviewing the guidelines and available evidence.

Adam Cifu

Many of us have had the experience of getting “routine X-rays” at a dentist visit before an examination or perhaps even before meeting a new dentist. Saying no to regular X-rays may incur disapproval, signing a waiver, or even discharge from the dental practice. I’ve never signed consent for a dental X-ray -- only for refusing one. It made me wonder: what evidence supports routine dental X-rays for people at low risk of caries (tooth decay)?

How common are dental X-rays?

In 2016, 320 million dental imaging procedures were done in the US, amounting to more than 46% of US diagnostic and nuclear imaging. Worldwide, dental radiography comprised about one-third of global diagnostic radiological examinations in 2020, or approximately one billion dental X-rays per year.

What is the evidence about using routine screening dental x-rays to detect caries?

There is little high-quality evidence regarding clinical outcomes, such as infection or tooth loss, related to screening X-rays for people at low risk of caries. Most dental research about X-rays has addressed malignancy risks or compared different radiologic techniques. Therefore, guidelines about screening X-rays for low-risk patients are mainly based on expert opinion.

A 2021 Cochrane review that included 77 studies (multinational data; 15,518 tooth sites or surfaces) concluded that low-certainty evidence suggested that imaging for the detection or diagnosis of early tooth decay may result in a relatively high proportion of false-negative results.

One secondary analysis of a randomized controlled trial of 216 preschool children concluded that the use of radiographs for caries detection was associated with more harms than benefits due to false positives, overdiagnosis, and lead-time bias. The trial compared visual-tactile examination alone to visual-tactile examination plus radiography.

A 2025 systematic review looked at the negative health effects of dental X-rays and concluded that none of the selected studies passed a quality assessment due to high or very high risk of bias.

What do guidelines say about dental X-rays and radiation exposure?

US, UK, and European guidelines advise an individualized approach to screening X-rays for people at low risk of caries. They advise that X-rays should be done following a clinical exam. Various advocacy efforts in the US and Europe have aimed at minimizing cumulative radiation exposure. These include Image Gently® (children), Image Wisely® (adults), as low as reasonably achievable (ALARA), and as low as diagnostically achievable, being indication-oriented and patient-specific (ALADAIP).

What do US guidelines say about dental X-ray frequency for people at low risk of caries?

The American Dental Association (ADA) in its 2012 guidelines advised that adults without signs and symptoms of oral disease who receive regular dental care are at low risk for caries. But the guidelines still recommended that low-risk adult recall patients receive bitewing X-rays every 2 to 3 years. Posterior bitewing exams every 1 to 2 years were recommended for children with primary dentition if proximal surfaces could not be examined visually or with a probe. In its follow-up 2024 systematic review, the ADA did not readdress guideline intervals.

What do international guidelines say about the frequency of dental X-rays for people at low risk of caries?

UK guidelines were mainly in agreement with those in the US. European pediatric guidelines recommended no X-ray screening for children under age 13 with primary dentition; every 3 to 5 years from ages 13 to 16; and every 5 to 10 years after age 16.

Are routine dental X-rays just an American issue?

Not entirely. Although the US is the largest market for the global share of dental X-rays, Asia is the fastest-growing market.

A Brazilian group led by Paul Nadanovsky has played a major role in addressing overdiagnosis and overtreatment in dentistry. The group has pointed out that the focus of studies of dental radiography should be the effectiveness of X-rays, rather than the accuracy of radiography in detecting early non-cavitated lesions. This was because evidence is lacking about whether such detection (with or without X-rays) is of clinical benefit.

What are some obstacles to change?

At a 2025 Oxford, UK conference on Overdiagnosis and Overtreatment, dentistry was identified as one of the top three areas for future focus (along with psychiatry and women’s health). Barriers to change include:

• Lack of evidence about outcomes related to routine X-rays for people at low risk for caries

• Assumption that low radiation dose justifies routine X-rays

• Radiographs were performed in the same setting as the clinical assessment

• X-rays are usually performed before the clinical exam

• Legal concerns

• Financial incentives are applicable

What should be the research going forward?

Dr. Nadanovsky’s group has suggested that the randomized trial in children mentioned above be followed up with similar trials in other age groups with permanent dentition. They have proposed that future studies should include a control group that does not undergo detection of non-cavitated lesions, forgoing both visual-tactile examination and radiography.

Other areas for study might include:

• Screening in the post-sealant, post-fluoride era

• Fixed vs. flexible screening intervals

• Modeling the redistribution of resources currently allocated to the radiographic screening of low-risk people

• Non-radiological screening techniques for caries detection

Conclusion

The practice of routine screening dental X-rays for people at low risk of caries deserves further research. Randomized trials are ethical and warranted. The trials should include objective, clinical endpoints, and should assess screening intervals as well as the need for screening X-rays at all.

Routine dental X-rays are so ingrained in dentists’ and the public’s consciousness that no one really questions the basis for them -- until someone does.

Sheila Feit, MD, attended the Mount Sinai School of Medicine and is a board-certified internist and endocrinologist. After clinical practice with a focus on women’s healthcare, she gained extensive experience in the medical publishing field, developing digital and educational tools for doctors and patients.

Photo Credit: Jonathan Borba