title: Effective dose span of ten different cone beam CT devices.
abstract: OBJECTIVE
  Evaluation and reduction of dose are important issues. Since cone beam CT (CBCT) has been established now not just in dentistry, the number of acquired examinations continues to rise. Unfortunately, it is very difficult to compare the doses of available devices on the market owing to different exposition parameters, volumes and geometries. The aim of this study was to evaluate the spans of effective doses (EDs) of ten different CBCT devices.
  
  
  METHODS
  48 thermoluminescent dosemeters were placed in 24 sites in a RANDO(®) head phantom. Protocols with lowest exposition parameters and protocols with highest exposition parameters were performed for each of the ten devices. The ED was calculated from the measured energy doses according to the International Commission on Radiological Protection 2007 recommendations for each protocol and device, and the statistical values were evaluated afterwards.
  
  
  RESULTS
  The calculation of the ED resulted in values between 17.2 µSv and 396 µSv for the ten devices. The mean values for protocols with lowest and highest exposition parameters were 31.6 µSv and 209 µSv, respectively.
  
  
  CONCLUSIONS
  It was not the aim of this study to evaluate the image quality depending on different exposition parameters but to define the spans of EDs in which different CBCT devices work. There is a wide span of ED for different CBCT devices depending on the selected exposition parameters, required spatial resolution and many other factors.
authors.affiliation: Dental Diagnostic Center, 79098 Freiburg, Germany. dennis.rottke@ddz-breisgau.de
authors.forename: D
authors.initials: D
authors.lastname: Rottke
authors.forename: S
authors.initials: S
authors.lastname: Patzelt
authors.forename: P
authors.initials: P
authors.lastname: Poxleitner
authors.forename: D
authors.initials: D
authors.lastname: Schulze
mesh_terms: D002138:Calibration; D002574:Cervical Vertebrae / Q000528:radiation effects; D002610:Cheek / Q000528:radiation effects; D054893:Cone-Beam Computed Tomography / Q000295:instrumentation* / Q000379:methods; D004947:Esophagus / Q000528:radiation effects; D006257:Head / Q000528:radiation effects; D006801:Humans; D007908:Lens, Crystalline / Q000528:radiation effects; D008334:Mandible / Q000528:radiation effects; D008636:Mesencephalon / Q000528:radiation effects; D009915:Orbit / Q000528:radiation effects; D010306:Parotid Gland; D019047:Phantoms, Imaging; D010902:Pituitary Gland / Q000528:radiation effects; D011829:Radiation Dosage; D019291:Skull Base / Q000528:radiation effects; D013361:Sublingual Gland / Q000528:radiation effects; D013363:Submandibular Gland / Q000528:radiation effects; D013819:Thermoluminescent Dosimetry / Q000295:instrumentation; D013961:Thyroid Gland / Q000528:radiation effects
keywords: cone beam computed tomography; dose range; effective doses; thermoluminescent dosimetry