title: Low-dose protocol of the spiral CT in orthodontics: comparative evaluation of entrance skin dose with traditional X-ray techniques.
abstract: BACKGROUND
  The aim of this study was to evaluate the amount of radiation doses absorbed by soft tissues (entrance skin dose) with a low-dose spiral computed tomography (CT) protocol compared to conventional X-ray techniques commonly used in orthodontics.
  
  
  METHODS
  The amount of skin dose has been evaluated using a tissue-equivalent head-neck radiotherapy humanoid phantom with thermoluminescent dosimeters placed at the level of eye lens, parotid glands, and thyroid glands. CT images have been taken using a Sensation 16 Siemens CT scan and a low-dose protocol (15 mAs, 1 pitch, 2.5 mGy (CTDIvol), 80 kV, 1-mm slice thickness).
  
  
  RESULTS
  The difference in image quality between traditional X-ray techniques and low-dose spiral CT was statistically significant (P<0.05). The difference in mean absorbed dose instead was not statistically significant.
  
  
  CONCLUSIONS
  Our protocol allows a more accurate orthodontic diagnosis without an increase of radiological risk for the patients in comparison to traditional X-ray techniques.
authors: Department of Orthodontics, University of Messina, Via Consolare Valeria, Messina 98100, Italy. marcoportelli79@tin.it.
authors: Giancarlo
authors: G
authors: Cordasco
authors: Marco
authors: M
authors: Portelli
authors: Angela
authors: A
authors: Militi
authors: Riccardo
authors: R
authors: Nucera
authors: Antonino
authors: A
authors: Lo Giudice
authors: Elda
authors: E
authors: Gatto
authors: Alessandra
authors: A
authors: Lucchese
mesh_terms: D059925:Anatomic Landmarks / Q000000981:diagnostic imaging; D002508:Cephalometry / Q000379:methods; D002680:Chin / Q000000981:diagnostic imaging; D006801:Humans; D007908:Lens, Crystalline / Q000528:radiation effects; D008334:Mandible / Q000000981:diagnostic imaging; D008335:Mandibular Condyle / Q000000981:diagnostic imaging; D008437:Maxilla / Q000000981:diagnostic imaging; D009295:Nasal Bone / Q000000981:diagnostic imaging; D009296:Nasal Cavity / Q000000981:diagnostic imaging; D009971:Orthodontics, Corrective; D010306:Parotid Gland / Q000528:radiation effects; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement / Q000379:methods; D011861:Radiography, Dental / Q000379:methods*; D011862:Radiography, Panoramic / Q000379:methods; D012658:Sella Turcica / Q000000981:diagnostic imaging; D012867:Skin / Q000528:radiation effects*; D013819:Thermoluminescent Dosimetry / Q000295:instrumentation; D013961:Thyroid Gland / Q000528:radiation effects; D015898:Tomography Scanners, X-Ray Computed / Q000145:classification; D036542:Tomography, Spiral Computed / Q000379:methods*; D015050:Zygoma / Q000000981:diagnostic imaging