Imaging Science in Dentistry

Korean Academy of Oral and Maxillofacial Radiology (대한영상치의학회)
권호 표지

Comparison of cone beam CT and conventional CT in absorbed and effective dose

Cone beam CT와 일반 CT의 흡수선량 및 유효선량 비교평가

  • Kim, Sang-Yeon (Department of Oral and Maxillofacial Radiology, College of Dentistry, Kangnung National University & Research Institute of Oral Science) ;
  • Han, Jin-Woo (Department of Oral and Maxillofacial Radiology, College of Dentistry, Kangnung National University & Research Institute of Oral Science) ;
  • Park, In-Woo (Department of Oral and Maxillofacial Radiology, College of Dentistry, Kangnung National University & Research Institute of Oral Science)
  • 김상연 (강릉대학교 치과대학 구강악안면방사선학교실 및 구강과학연구소) ;
  • 한진우 (강릉대학교 치과대학 구강악안면방사선학교실 및 구강과학연구소) ;
  • 박인우 (강릉대학교 치과대학 구강악안면방사선학교실 및 구강과학연구소)
  • Published : 2008.03.31
Download PDF
⟨ Previous Next ⟩

Abstract

Purpose: This study provides comparative measurements of absorbed and effective doses for newly developed cone beam computed tomography (CT) in comparison with these doses for conventional CT. Materials and Methods: Thermoluminescent dosimeter rods (TLD rod: GR-200, Thermo Fisher Scientific Inc., Waltham, MA, USA) were placed at 25 sites throughout the layers of Male ART Head and Neck Phantom (Radiology Support Devices Inc., Long Beach, USA) for dosimetry. Implagraphy, DCT Pro (Vatech Co., Hwasung, Korea) units, SCT-6800TXL (Shimadzu Corp., Kyoto, Japan), and Crane x 3+(Soredex Orion Corp., Helsinki, Finland) were used for radiation exposures. Absorption doses were measured with Harshaw 3500TLD reader (Thermo Fisher Scientific Inc., Waltham, MA, USA). Radiation weighted doses and effective doses were measured and calculated by 2005 ICRP tissue weighting factors. Results: Absorbed doses in Rt. submandibular gland were 110.57 mGy for SCT 6800TXL (Implant), 24.56 mGy for SCT 6800TXL (3D), 22.39 mGy for Implagraphy 3, 7.19 mGy for DCT Pro, 5.96 mGy for Implagraphy 1, 0.70 mGy for Cranex 3+. Effective doses $(E_{2005draft)$ were 2.551 mSv for SCT 6800TXL (Implant), 1.272 mSv for SCT 6800TXL (3D), 0.598 mSv for Implagraphy 3, 0.428 mSv for DCT Pro and 0.146 mSv for Implagraphy 1. These are 108.6, 54.1, 25.5, 18.2 and 6.2 times greater than panoramic examination (Cranex 3+) doses (0.023mSv). Conclusion: Cone beam CT machines recently developed in Korea, showed lower effective doses than conventional CT. Cone beam CT provides a lower dose and cost alternative to conventional CT, promising to revolutionize the practice of oral and maxillofacial radiology.

Keywords