title: Evaluation of the effective dose of cone beam CT and multislice CT for temporomandibular joint examinations at optimized exposure levels.
abstract: OBJECTIVE
  To compare the effective dose to patients from temporomandibular joint examinations using a dental CBCT device and a multislice CT (MSCT) device, both before and after dose optimization.
  
  
  METHODS
  A Promax(®) 3D (Planmeca, Helsinki, Finland) dental CBCT and a LightSpeed VCT(®) (GE Healthcare, Little Chalfont, UK) multislice CT were used. Organ doses and effective doses were estimated from thermoluminescent dosemeters at 61 positions inside an anthropomorphic phantom at the exposure settings in clinical use. Optimized exposure protocols were obtained through an optimization study using a dry skull phantom, where four observers rated image quality taken at different exposure levels. The optimal exposure level was obtained when all included criteria were rated as acceptable or better by all observers.
  
  
  RESULTS
  The effective dose from a bilateral examination was 184 µSv for Promax 3D and 113 µSv for LightSpeed VCT before optimization. Post optimization, the bilateral effective dose was 92 µSv for Promax 3D and 124 µSv for LightSpeed VCT.
  
  
  CONCLUSIONS
  At optimized exposure levels, the effective dose from CBCT was comparable to MSCT.
authors.affiliation: 1 Oral Facial Diagnostics and Surgery, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden.|2 Medical Radiation Physics, Karolinska University Hospital, Huddinge, Sweden.
authors.forename: N
authors.initials: N
authors.lastname: Kadesjö
authors.affiliation: 1 Oral Facial Diagnostics and Surgery, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden.
authors.forename: D
authors.initials: D
authors.lastname: Benchimol
authors.affiliation: 3 Department of Radiology in Huddinge, Karolinska University Hospital, Huddinge, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Falahat
authors.affiliation: 1 Oral Facial Diagnostics and Surgery, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Näsström
authors.affiliation: 1 Oral Facial Diagnostics and Surgery, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden.
authors.forename: X-Q
authors.initials: XQ
authors.lastname: Shi
mesh_terms: D001853:Bone Marrow / Q000000981:diagnostic imaging; D001921:Brain / Q000000981:diagnostic imaging; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D004947:Esophagus / Q000000981:diagnostic imaging; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging; D008334:Mandible / Q000000981:diagnostic imaging; D009061:Mouth Mucosa / Q000000981:diagnostic imaging; D061330:Multidetector Computed Tomography / Q000379:methods*; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement / Q000379:methods; D012062:Relative Biological Effectiveness; D012796:Sialography / Q000379:methods; D012886:Skull / Q000000981:diagnostic imaging; D013704:Temporomandibular Joint / Q000000981:diagnostic imaging*; D013819:Thermoluminescent Dosimetry / Q000379:methods; D013961:Thyroid Gland / Q000000981:diagnostic imaging
keywords: cone beam computed tomography; temporomandibular joint; thermoluminescent dosimetry