Determination of relative dose of ionizing radiation in the thyroid gland using a panoramic device with different protocols.

BACKGROUND: The use of panoramic radiography (PR) is a complementary examination to aid in the diagnosis of cases in paediatric dentistry. The lack of specific protocols for these devices, however, can result in high doses of radiation, affecting critical organs such as the thyroid. AIM: To evaluate the discrepancies in ionizing radiation received by the thyroid during PR examinations using anthropomorphic paediatric simulators built from computed tomography images. DESIGN: Two anthropomorphic paediatric phantoms were printed and used, representing children aged 6 and 11 years, with an opening in the thyroid region for the insertion of dosimetric radiographic films. The simulators were subjected to different pre-existing protocols in the PR devices. The radiographic films were processed and analysed using a luxmeter. RESULTS: The radiation dose to the thyroid was higher in the 6-year-old phantom than in the 11-year-old phantom, for given exposure factors. In addition, there was an increase in dose in children's protocols compared with small adult protocols. CONCLUSION: Therefore, companies that develop PR equipment must develop child protocols for separate age groups that will consequently reduce the radiation dose in children, especially in their critical organs.

Development of an open project rectangular collimator for use with intraoral dental X-ray unit.

In this work, an open beam-limiting device, consisting of a rectangular collimator to be coupled to an intraoral dental X-ray device, was made using recycled lead sheets as a radiation-absorbing element. The collimator was designed for 3D printing, and using Spektr 3.0 software, the number of lead sheets needed to absorb excess radiation was calculated. The rectangular collimator reduced the radiation dose to patients by 65% when using four layers of recycled lead sheets (saturating with a 70% reduction in radiation dose at the limit of eight or more sheets of lead). The rectangular collimator does not negatively impact the quality of the radiological image, is available as an open design for 3D printing, and can be built with materials that are easily accessible to the dentist, facilitating its use in clinical practice and reducing the patient's exposure to ionizing radiation.