Using GafChromic film to estimate the effective dose from dental cone beam CT and panoramic radiography

Abstract

Objectives: To demonstrate the feasibility of GafChromic ® XR-QA2 (ISP Corp., Wayne, NJ) as a dosemeter when performing measurements of the effective dose from three cone beam CT (CBCT) units and to compare the doses from examinations of three common dental clinical situations. A second aim was to compare the radiation doses for three digital panoramic units with the doses for the CBCT units. Methods: The CBCT units used were Veraviewepocs 3De ® (J Morita MFG Corp., Kyoto, Japan), ProMax ® 3D (Planmeca, Helsinki, Finland) and NewTom VGi ® (Quantitative Radiology, Verona, Italy). GafChromic XR-QA2 films were placed between the selected layers of the head and neck of a tissue-equivalent human skull (RANDO ® phantom; The Phantom Laboratory, Salem, NY). The exposure parameters were set using the automatic exposure control function of the units. Depending on the availability, medium and smaller field of view (FOV) scanning modes were used. The effective dose was estimated using the 2007 International Commission on Radiological Protection formalism. Results: The lowest effective dose of a CBCT unit was observed for ProMax 3D, FOV 4 3 5 cm (10 mSv), the highest for NewTom VGi, FOV 8 3 8 cm-high resolution (129 mSv). The range of effective doses for digital panoramic machines measured was 8-14 mSv. Conclusions: This study demonstrates the feasibility of using radiochromic films for dental CBCT and panoramic dosimetry.

Effective dose of cone beam CT (CBCT) of the facial skeleton: a systematic review

“…The dose of FOVs of ,10 cm was higher for examination of the lower jaw than for the upper jaw 23,30 and for examinations with the FOV positioned on the posterior part of the lower jaw than for the anterior part of the upper jaw. 14,38,45 The effective dose was reduced by 43% when 0.4-mm copper filtration was added in examinations with FOV heights 9 and 18 cm. 18 Effective dose was related to image quality in six studies (Table 2) expressed as objective image quality 21,32,39,40 or subjective image quality.…”

kVp estimate intercomparison between Unfors XI, Radcal 4075 and a new CDTN multipurpose instrument

“…For the range of energy selected by the authors, the dependence on energy remained below 10%. Al-Okshi et al (2013) found virtually coincident dose-response curves when testing the Gafchromic s XR-QA2 film for 60 kV, 80 kV and 120 kV beams, which suggests weak dependence on energy within the selected energy range.…”

Evaluation of symptomatic maxillary sinus pathologies using panoramic radiography and cone beam computed tomography—influence of professional training

“…Especially if small fields of view are used for CBCT, radiation exposure is significantly reduced. However, this exposure to radiation as well as the costs are still significantly higher when compared to those of conventional dental imaging [19–22]. For diagnosis and general preoperative planning, both PAN and CBCT are described to be useful and important diagnostic tools [11, 23, 24].…”