Assessment of the effective doses from two dental cone beam CT devices

Abstract

Objectives: This study compares the effective dose for different fields of view (FOVs), resolutions and X-ray parameters from two cone beam CT units: the KaVo 3D (threedimensional) eXam and the KaVo Pan eXam Plus 3D (KaVo Dental, Biberach, Germany). Methods: Measurements were made using thermoluminescent dosemeter chips in a radiation analog dosimetry head and neck phantom. The calculations of effective doses are based on the ICRP 60 and ICRP 103 recommendations of the International Commission on Radiological Protection. Results: Effective doses from the 3D eXam ranged between 32.8 mSv and 169.8 mSv, and for the Pan eXam Plus effective doses ranged between 40.2 mSv and 183.7 mSv; these were measured using ICRP 103 weighting factors in each case. The increase in effective dose between ICRP 60 and ICRP 103 recommendations averaged 157% for all measurements. Conclusions: Effective doses can be reduced significantly with the choice of lower resolutions and mAs settings as well as smaller FOVs to avoid tissues sensitive to radiation being inside the direct beam. Larger FOVs do not necessarily lead to higher effective doses.

Assessment of Apical Periodontitis by MRI: A Feasibility Study

“…Using the conventional Xray techniques, it is not possible to distinguish a radicular cyst from a chronic apical granuloma, which may have an impact on the treatment regimen. Thus, the image quality of the panoramic radiography is clearly limited in its expressiveness and its use can only be justified by the low effective radiation dose [52]. To address these ambiguities, the investigators have moved along to three-dimensional imaging with CBCT [13,14].…”

Effective radiation dose and eye lens dose in dental cone beam CT: effect of field of view and angle of rotation

“…28 The field of view (FOV) and its position relative to the radiosensitive organs are key factors determining the radiation dose to the patient. [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] In addition, some CBCT scanners expose using a full 360°rotation, whilst others use rotation angles between 180°and 220°. Although the relationship between FOV, organ doses and effective dose has not yet been quantified, a larger FOV will capture more tissue in the primary X-ray beam and increase the scattered radiation dose to the surrounding tissues.…”

Absorbed doses in salivary and thyroid glands from panoramic radiography and cone beam computed tomography

“…The anatomic distribution was based on the fraction irradiated organ during a panoramic radiograph and a CBCT scan, on which we decided to choose those that were 100% irradiated (Ludlow and Ivanovic, 2008) and those that received the highest effective doses in previous studies (Loubele et al, 2009). Following the statement of reflect critical organs known to be sensitive to radiation (Ludlow and Ivanovic, 2008;Schilling and Geibel, 2013). Since TLDs are sensible to any source of background radiation (BG) while being transported, or in the ionizing equipment room, this radiation was also measured in order to discount it from de absorb dose in each TLD placed in the phantom.…”