Program including abstracts as pdf available here

OP 67
Title
DOSIMETRy OF THREE CbCT DEVICES uSING RADIOCHROMIC FILM
Authors
A. AL-OKSHI 1 , M. NILSSON 1 , A. PETERSSON 1,2 , M. WIESE 2 , C. LINDH 1
Affiliations
1 Departnet of Oral and Maxillofacial Radiology, Faculty of Odontology, Malmö University,
Malmö, SWEDEN, 2 Department of Oral Radiology, School of Dentistry, University of
Copenhagen, Copenhagen, DENMARK
Body
Objective Cone Beam Computed Tomography (CBCT) is being used with increasing frequency in
the practice of Oral and Maxillofacial Radiology. The radiation doses to patients vary between
machines depending on differences in exposure parameters and there is a wide range of effective
doses reported for CBCT devices. To provide comparative measurements of the effective
dose from the CBCT devices Veraviewpocs 3De, ProMax 3D and NewTom VGi, and to compare
the doses from examinations of three clinical situations by the use of radiochromic film as
dosimeter.
Methods Radiochromic films (Gafchromic® XR-QA 2) were placed between selected layers of
the head and neck of a tissue-equivalent human skull (RANDO phantom). Depending on availability,
medium and smaller FOV scanning modes were used. Effective dose was estimated using
the 2007 ICRP formalism. Exposure parameters were set by the automatic exposure control
function of the units.
Results The lowest effective dose was observed for ProMax 3D 5x4 cm ( 9 µSv),the highest for
the NewTom VGi 8x8 cm – high resolution (118 µSv).
Veraviewepocs 3 De
4x4 cm Anterior Maxilla Standard 20µSV
4x4 cm Posterior Mandible Standard 19µSV
ProMax 3D
5x4 cm Anterior Mandible Standard 9µSV
NewTom VGi
8x8 cm TMJ – Standard 43µSV
8x8 cm TMJ – High 118µSV
8x12cm TMJ – Zoom mode 48µSV
Conclusions CBCT dose varies substantially depending on the device, FOV, and selected resolution
factor. This study also demonstrates the feasibility of using radiochromic films for dental
CBCT dosimetry.
Keywords
Cone Beam CT, Radiation dosage, Film dosimetry
72