title: Effective doses from cone beam CT investigation of the jaws.
abstract: OBJECTIVE
  The purpose of the study was to calculate the effective dose delivered to the patient undergoing cone beam (CB) CT of the jaws and maxillofacial complex using the i-CAT Next Generation CBCT scanner (Imaging Sciences International, Hatfield, PA).
  
  
  METHODS
  A RANDO® phantom (The Phantom Laboratory, Salem, NY) containing thermoluminence dosemeters were scanned 10 times for each of the 6 imaging protocols. Effective doses for each protocol were calculated using the 1990 and approved 2007 International Commission on Radiological Protection (ICRP) recommended tissue weighting factors (E1990, E2007).
  
  
  RESULTS
  The effective dose for E1990 and E2007, respectively, were: full field of view (FOV) of the head, 47 μSv and 78 μSv; 13 cm scan of the jaws, 44 μSv and 77 μSv; 6 cm standard mandible, 35 μSv and 58 μSv; 6 cm high resolution mandible, 69 μSv and 113 μSv; 6 cm standard maxilla, 18 μSv and 32 μSv; and 6 cm high resolution maxilla, 35 μSv and 60 μSv.
  
  
  CONCLUSIONS
  Using the new generation of CBCT scanner, the effective dose is lower than the original generation machine for a similar FOV using the ICRP 2007 tissue weighting factors.
authors.affiliation: Department of Dental Radiological Imaging, Kings College London Dental Institute, London, UK. jonathan.davies@kcl.ac.uk
authors.forename: J
authors.initials: J
authors.lastname: Davies
authors.forename: B
authors.initials: B
authors.lastname: Johnson
authors.forename: Na
authors.initials: N
authors.lastname: Drage
mesh_terms: D001921:Brain / Q000528:radiation effects; D054893:Cone-Beam Computed Tomography / Q000295:instrumentation / Q000379:methods*; D005147:Facial Bones / Q000000981:diagnostic imaging / Q000528:radiation effects; D006801:Humans; D008334:Mandible / Q000000981:diagnostic imaging / Q000528:radiation effects*; D008437:Maxilla / Q000000981:diagnostic imaging / Q000528:radiation effects*; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D012062:Relative Biological Effectiveness; D019291:Skull Base / Q000528:radiation effects; D013363:Submandibular Gland / Q000528:radiation effects; D013819:Thermoluminescent Dosimetry / Q000295:instrumentation; D013961:Thyroid Gland / Q000528:radiation effects