Low-dose protocol of the spiral CT in orthodontics: comparative evaluation of entrance skin dose with traditional X-ray techniques

Prog Orthod. 2013 Sep 10:14:24. doi: 10.1186/2196-1042-14-24.

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.

Publication types

  • Comparative Study

MeSH terms

  • Anatomic Landmarks / diagnostic imaging
  • Cephalometry / methods
  • Chin / diagnostic imaging
  • Humans
  • Lens, Crystalline / radiation effects
  • Mandible / diagnostic imaging
  • Mandibular Condyle / diagnostic imaging
  • Maxilla / diagnostic imaging
  • Nasal Bone / diagnostic imaging
  • Nasal Cavity / diagnostic imaging
  • Orthodontics, Corrective*
  • Parotid Gland / radiation effects
  • Phantoms, Imaging
  • Radiation Dosage*
  • Radiographic Image Enhancement / methods
  • Radiography, Dental / methods*
  • Radiography, Panoramic / methods
  • Sella Turcica / diagnostic imaging
  • Skin / radiation effects*
  • Thermoluminescent Dosimetry / instrumentation
  • Thyroid Gland / radiation effects
  • Tomography Scanners, X-Ray Computed / classification
  • Tomography, Spiral Computed / methods*
  • Zygoma / diagnostic imaging