Explaining the Safety of Dental Radiography

We’ve come a long way since Wilhelm Conrad Röntgen, a German mechanical engineer and physicist, discovered X-rays in 1895. At that time, radiography was considered a miracle because, for the first time, clinicians could see inside the body without surgery.¹ It took several years before the dangers of this new technology became known.

George Eastman, an American entrepreneur and founder of Eastman Kodak Co who revolutionized the field of photography, created an intraoral film packet for dental X-rays. At this point, a single exposure time was 8 to 9 seconds.² Today, with the use of digital imaging, the exposure time for a single intraoral image has been reduced to milliseconds.

The field of dentistry relies on various imaging techniques, each serving a specific purpose in diagnosing and evaluating conditions of the head and neck and the oral cavity. The judicious selection of these techniques is essential to ensure adequate diagnosis while minimizing potential risks.

Radiation Exposure Concerns

As the dangers of ionizing radiation became evident, researchers and healthcare professionals have worked to minimize these risks. Excess radiation exposure, whether from natural (eg, the sun) or from artificial (eg, X-rays) sources, can cause somatic damage. Curiously, patients seem to have less concern about sun damage than any issues with X-ray exposure — both of which are caused by ionizing radiation.

Patients are concerned about radiation exposure. Qari et al³ conducted a phonological study on the topic that included 105 participants. Approximately 22% of respondents showed specific concerns regarding dental imaging. Another 20% expressed skepticism, suggesting that many respondents may be uncertain about the safety and necessity of dental imaging.

Beneke et al⁴ found that open communication addressing a patient’s emotional and factual resistance to X-rays is critical to building trust and ensuring that patients are well-informed about the risks and benefits associated with dental imaging. Addressing patient concerns about ionizing radiation exposure in dental X-rays requires effective communication and education.

Following are strategies that healthcare professionals can use to convey information about the stochastic effects of dental X-rays to patients in a clear and reassuring manner.

Advancements in Technology

Advancements in imaging technology, such as digital radiography, have indeed helped to reduce radiation doses and improve image quality in medical diagnostics. Digital radiography offers faster image acquisition and the ability to manipulate images for better visualization and eliminate film processing steps.⁵

One advancement in digital imaging is rectangular collimation, which limits the amount of primary and scattered radiation exposure to the patient.⁶ Rectangular collimation provides improved image contrast with less fogging from scattered radiation. It also helps prevent misaligned images such as cone cutting.

Another advancement is the lower radiation dose, which produces higher image contrast.⁷ Dental practitioners should strive to set the exposure time to the lowest possible setting for diagnostic contrast. Most dental X-ray units have an optimal dose of 60 to 70 kVp.⁸Portable, self-contained, cordless, hand-held X-ray units are often used for intraoral radiographs; they can be used in nursing homes, hospitals, and situations where a wall-mounted X-ray unit cannot be utilized (Figures 1 and 2).⁹ Research shows handheld devices pose no greater radiation risk to the patient and operator than a traditional wall-mounted dental X-ray unit.¹⁰

The annual maximum permissible dose (MPD) of radiation is 50 mSv (5,000 mrem). Data using the MPD have determined that the radiation exposure using a handheld radiography device is lower.¹¹ The operator should be appropriately trained in hand-held X-ray units to prevent overexposure to themselves and their patients.

Strategic Patient Education

When reassuring patients regarding the safety of dental radiography, avoid technical jargon and use simple, easily understandable language to explain the concepts. Describe radiation exposure in everyday terms to enhance comprehension.

The use of analogies can be helpful; for example, relate the radiation exposure from dental X-rays to everyday activities or natural background radiation. Clinicians may explain that a dental X-ray is comparable to the amount received from a day of natural background radiation.

Clinicians may also want to highlight the fact that the radiation doses in dental X-rays are typically low and carefully controlled to minimize any potential risk. Compare dental X-ray doses to other medical imaging procedures, emphasizing their relative safety.

Patients also need to understand the benefits of obtaining diagnostic information from dental X-rays and how this information contributes to effective treatment planning. Emphasize the importance of the knowledge gained vs the low associated risk.

Advancements in dental imaging technology and techniques that have reduced radiation doses should be explained. Mention that newer equipment and methods are designed to deliver the necessary diagnostic information with lower radiation exposure.

Encourage patients to ask questions and express their concerns. Addressing their specific worries can help alleviate anxiety and build trust in the dentist’s and dental hygienist’s expertise.

Visual aids may also enhance patient understanding and acceptance. Incorporating diagrams, charts, or videos can help to illustrate difficult and complex concepts. Visualizing the information can promote greater understanding and retention.

Patients should be provided with informed consent forms that clearly outline the nature of the procedure, associated risks, and benefits.¹² This empowers patients to make informed decisions about their healthcare.

Dental professionals should provide information in a way that allows for follow-up questions and continued discussion. Reassure patients that their concerns are valid, and that staff members are available to address any further queries.

By employing these communication strategies, dental providers can help demystify the stochastic effects of dental X-rays, alleviate patient concerns, and foster a sense of trust and collaboration in the healthcare decision-making process.

Professional Guidelines and Recommendations

Clinicians and patients are best served when a practice is guided by evidence-based decision-making. Such a dental practice combines the clinician’s expertise, the patient’s dental and medical history, and scientific findings.¹³ Patients with higher caries risk may need more frequent dental imaging than those with lower caries risk, until the higher caries activity is controlled. Many dental practitioners have adopted an evidence-based approach to patient care. Recognizing that all patients are unique and tailoring the communication and practice to their individual needs will be effective.

Every state has laws and regulations governing medical and dental imaging or ionizing radiation. The laws and regulations may include the following:⁸

• Inspection and testing
• Lead apron usage
• Permit or licensing
• Training or certification

Dental professionals must adhere to the laws and regulations of their respective states to ensure their own safety and that of their patients.

Professional Guidelines and Recommendations

The American Dental Association (ADA) has recently updated its 2012 recommendations for radiation safety in dentistry.¹⁴ The highlights of these evidence-based best practices are:¹⁵

• Digital imaging should be used over conventional X-ray film.
• The beam size should be restricted with rectangular collimation.
• The use of lead aprons and thyroid collars (even during pregnancy) are no longer necessary.

As always, exposure should be limited to the greatest degree possible. This encompasses taking as few exposures as possible, using cone-beam computed tomography only when diagnostically necessary, following all standard practices for safe and efficient exposures, and adhering to all federal, state and local laws and guidelines.

For clinicians looking for resources demonstrating the safety of dental imaging, the Journal of the American Dental Association published a brief article, written for patients, on the value of dental X-rays. It is available at no cost at jada.ada.org.¹⁶

Determining when to capture dental radiographs is based on a variety of factors. The ADA and the United States Food and Drug Administration recommend bitewings be captured every 24 to 36 months for patients with a low risk of decay. Patients at elevated caries risk should have bitewings taken every 6 to 18 months.

A full-mouth series or panoramic radiograph can be taken every 3 to 5 years based on patient need. The maximum number of radiographs per year is determined by the patient’s decay risk, periodontal health, oral hygiene habits, and overall health issues.¹⁷

Conclusion

Ongoing discussions, research, and professional education are crucial to address patient concerns surrounding radiation exposure during dental radiography. Open communication within the dental community, continuous training on radiation safety, and a commitment to patient-centered care can help strike a balance between obtaining necessary diagnostic information and ensuring the well-being of patients through minimized radiation exposure.

The dental field relies on various imaging techniques, each serving a specific purpose in diagnosing and evaluating oral conditions. The judicious selection of these techniques is essential to ensure adequate diagnosis while minimizing potential risks and providing a safe and healthful environment for both clinicians and patients.

References

1. History.com. The day in history: German scientist discovers X-rays. Available at: history.c/​m/​this-day-in-history/​german-scientist-discovers-x-rays. Accessed June 10, 2024.
2. Pauwels R. History of dental radiography: Evolution of 2D and 3D imaging modalities. Medical Physics International Journal. Special Issue, History of Medical Physics. 2020;Special Issue:235­–277.
3. Qari L, Homsi N, AlMadani T, et al. An assessment of the public’s perceptions of radiation exposure and risk associated with dental radiographs: A cross-sectional Study. Cureus. 2023;15(10):e47879.
4. Benecke M, Kasper J, Heesen C, Schäffler N, Reissmann DR. Patient autonomy in dentistry: demonstrating the role for shared decision making. BMC Med Inform Decis Mak. 2020;20:318.
5. Jayachandran S. Digital imaging in dentistry: a review. Contemp Clin Dent. 2017;8:193-194.
6. United States Food and Drug Administration. The Selection of Patients for Dental Radiographic Examinations. Available at: fda.gov/​radiation-emitting-products/​medical-x-ray-imaging/​selection-patients-dental-radiographic-examinations. Accessed June 10, 2024.
7. Lommen J, Schorn L, Nitschke J, et al. Accuracy in positioning of dental X-ray images – a comparative study of a portable X-ray device and a wall-mounted device. Saudi Dent J. 2021;33:884-889.
8. American Dental Association. Radiographic Imaging. Available at: ada.org/​resources/​practice/​practice-management/​radiographic-imaging. Accessed June 10, 2024.
9. Nitschke J, Schorn L, Holtmann H, et al. Image quality of a portable X-ray device (Nomad Pro 2) compared to a wall-mounted device in intraoral radiography. Oral Radiol. 2021;37:224-230.
10. Brooks SL, McMinn WE, Benavides E. A clinical trial of the Nomad portable X-ray unitJ J Mich Dent Assoc. 2009;91:54-58.
11. Danforth RA, Herschaft EE, Leonowich JA. Operator exposure to scatter radiation from a portable hand-held dental radiation emitting device (Aribex NOMAD) while making 915 intraoral dental radiographs. J Forensic Sci. 2009;54:415-21.
12. Hammond W. Informed Consent: Procedures, Ethics, and Best Practices. Hauppauge, New York: Nova Publishers; 2016.
13. Carrasco AL, Brignardello-Petersen R, Glick M, Azarpazhooh A, Guyatt G. How to Use Evidence-Based Dental Practices to Improve Your Clinical Decision-Making. Chicago: American Dental Association; 2020.
14. American Dental Association. ADA Releases Updated Recommendations to Enhance Radiography Safety in Dentistry. Available at: ada.org/​about/​press-releases/​ada-releases-updated-recommendations-to-enhance-radiography-safety-in-dentistry. Accessed June 10, 2024.
15. Benavides E, Krecioch J, Connolly R, et al. Optimizing radiation safety in dentistry clinical recommendations and regulatory considerations. J Am Dent Assoc. 2024;155:280-293.
16. Mark AM. The value of dental X-rays. J Am Dent Assoc. 2024;155:356.
17. United States Food and Drug Administration. The Selection of Patients for Dental Radiographic Examinations. Available at: fda.gov/​radiation-emitting-products/​medical-x-ray-imaging/​selection-patients-dental-radiographic-examinations. Accessed June 10, 2024.

From Decisions in Dentistry. June/July 2024; 10(4):20-23