Do Extraoral Imaging Systems Require the Use of a Lead Apron?

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There seems to be some disagreement among radiologists, dental professionals and state regulatory authorities about whether or not lead aprons are necessary when taking dental X-rays. In the case of digital dental extraoral imaging, such as panoramic, cephalometric or Dental Cone Beam scans, advances in technology have made it possible to produce high-quality images using lower radiation doses, making lead aprons obsolete and unnecessary in many cases.

When conventional dental X-rays were invented over a century ago, the equipment was not properly collimated and produced a large amount of radiation scatter during image exposure. This resultant scatter proposed a significant health risk to patients. The lead apron, designed to absorb most radiation scatter, provided a necessary level of protection to patients. Modern digital panoramic X-ray equipment, however, is designed to collimate, or concentrate, the X-rays to a precise area of interest, greatly reducing radiation scatter and virtually eliminating the need for additional patient shielding.

In 2019, the National Council of Radiation Protection and Measurements (NCRP) published updated guidelines and suggestions to dentists and dental specialists in Report No. 177, “Radiation Protection in Dentistry and Oral & Maxillofacial Imaging,” where it lists over 60 recommendations intended to limit a patient’s exposure to radiation based on ALARA (as low as reasonably achievable) principles. In addition to providing general safety guidelines, this report outlined updated guidance specifically on digital dental and CBCT (dental cone beam computed tomography) imaging including:

·         The use of appropriate selection for obtaining dental cone beam images

·         The use of the smallest field-of-view (FOV) and acquisition settings when capturing dental cone beam scans

·         The implementation of an “Image Gently” campaign, which outlines the risks of radiation exposure to children

·         The need for quality assurance protocol in digital dental imaging techniques

In Report No. 177, the NCRP states that “every effort should be made to reduce a patient’s exposure to radiation.” It also states that “ Technological and procedural improvements have eliminated the requirement for the radiation protective apron, provided all other recommendations of this Report are rigorously followed unless required by state regulation. However, some patients have come to expect the apron and may request that it be used.” That means that the NCRP suggests that, as long as all other recommendations have been followed, lead aprons are not necessarily required for dental imaging unless required by the state or if a patient feels more comfortable wearing one.

Regardless of recommendations from the NCRP and other radiation authorities, some states require dental practices to use lead aprons when capturing digital panoramic, ceph or dental cone beam images. California is one such state that requires the use of lead aprons during any type of dental radiography. For example, Title 17 of the California Code of Regulations (CCR) § 30311 states that “Each patient undergoing dental radiography shall be draped with a protective apron of not less than 0.25-millimeter lead-equivalent to cover the gonadal area.” Texas also requires that lead aprons be used, but provides additional guidance, as well. Title 22 of the Texas Administrative Code”, Part 5, Rule §113.2 states “All dental patients must be protected by a lead apron with the thyroid collar while directly exposed to X-rays with the exception of those radiographs where it is necessary to image areas concealed or obstructed by a thyroid collar. A non-lead apron may be used instead of a lead apron if the non-lead apron provides protection from X-rays that is equivalent to that of a lead apron.”

It is important, then, for each dental office to determine if their state requires the use of a lead apron during radiation exposure and under which conditions. Most of these rules can be found on each state’s X-ray regulation website or by contacting the state X-ray agency directly. If a lead apron is used for extraoral imaging, make sure that it does not interfere with the rotation of the panoramic, cephalometric or dental cone beam machine during exposure. Do not use a thyroid collar, unless required by the state, if it is in the direct rotation path of the imaging device. Lead interference during panoramic X-ray acquisition typically appears on the resultant image as white triangular artifacts. These artifacts can hinder image quality and thereby evaluation and diagnoses, often resulting in image retakes and additional exposure risk to the patient.

Further, unless required to use lead aprons by their state, each dental office should determine their patients’ psychological perception of protective aprons. Lead shielding has been commonplace in the dental practice for many years. Patients may feel apprehensive and unsafe if they are not shielded during exposure. Gauge whether or not your patients would feel more comfortable wearing the lead apron. Take every opportunity to educate them on the benefits of newer digital dental imaging technology used in your practice and why it is much safer than previous imaging devices and protocols.

Although it is unlikely that lead aprons are necessary when capturing dental extraoral X-rays or dental cone beam scans, we are still a long way from no longer using them in the dental office. Even if your practice decides to stop routinely draping patients, it is a good idea to give them the option of wearing lead shielding or not. This may be especially helpful for imaging patients that are pregnant, unwell, elderly or very young.

Renew Digital has been a trusted source for dental professionals for over a decade, providing high-quality, certified pre-owned panoramic, cephalometric and dental cone beam equipment up to 50% off list price of new systems. Plus, each used dental equipment purchase includes installation, training and a full onsite service and parts replacement warranty. For more information about the company and to get an up-to-date list of their available inventory, contact Renew Digital online or call 888-246-5611 today

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