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The aim of this literature review was to analyze the evidence and international recommendations on the use of thyroid shield (TS) in cone-beam computed tomography (CBCT) examinations. The search was conducted in three electronic databases (PubMed, Scopus, and Web of Science) in English from 2010 to date. This search included articles that provided recommendations or benefits of TS use in CBCT, as well as those that discouraged its use. A complementary search was conducted by reviewing guidelines, recommendations, or articles from international organizations and globally recognized journals, published on their official websites. Of the 23 articles reviewed, 19 indicate that using TS in CBCT reduces radiation doses in patients or recommend its use in these examinations, as it provides a benefit to the patient. However, some note specific cases where its use is not advised. On the other hand, two articles, from the British Institute of Radiology and the UK Health Security Agency, do not recommend the use of TS in CBCT examinations, except in specific cases. Finally, two articles, both from the American Dental Association, oppose TS use in all maxillofacial radiographic examinations, including CBCT. Although there is no consensus among the reviewed articles regarding recommendations or benefits of TS use in CBCT examinations, most articles indicate that it reduces ionizing radiation doses or recommend its use. However, in some cases, TS use may interfere with image quality, making deciding whether to use TS in CBCT examinations challenging for the operator.
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