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

• Published in: Dento-maxillo-facial radiology 2013-07, Vol.42 (7), p.20120343
• Main Authors: Al-Okshi, A, Nilsson, M, Petersson, A, Wiese, M, Lindh, C
• Format: Article
• Language: English
• Subjects: Brain - radiation effects; Calibration; Cervical Vertebrae - radiation effects; CONE BEAM COMPUTED TOMOGRAPHY; Cone-Beam Computed Tomography - instrumentation; Cone-Beam Computed Tomography - methods; Cuspid - diagnostic imaging; Dose-Response Relationship, Radiation; Feasibility Studies; FILM DOSIMETRY; Humans; Mandible - diagnostic imaging; Mandible - radiation effects; Maxilla - diagnostic imaging; Molar - diagnostic imaging; Mouth Mucosa - radiation effects; Parotid Gland - radiation effects; Phantoms, Imaging; RADIATION DOSAGE; Radiography, Dental, Digital - instrumentation; Radiography, Dental, Digital - methods; Radiography, Panoramic - instrumentation; Radiography, Panoramic - methods; Radiometry - instrumentation; Relative Biological Effectiveness; Skin - radiation effects; Temporomandibular Joint - diagnostic imaging; Thermoluminescent Dosimetry - instrumentation; Thyroid Gland - radiation effects; X-Ray Film - classification
• ISSN: 0250-832X; 1476-542X; 1476-542X
• DOI: 10.1259/dmfr.20120343

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. 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. The lowest effective dose of a CBCT unit was observed for ProMax 3D, FOV 4 × 5 cm (10 μSv), the highest for NewTom VGi, FOV 8 × 8 cm-high resolution (129 μSv). The range of effective doses for digital panoramic machines measured was 8-14 μSv. This study demonstrates the feasibility of using radiochromic films for dental CBCT and panoramic dosimetry.