Velders X L, Sanderink G C, van der Stelt P F
Department of Oral Radiology, Academic Centre for Dentistry, Amsterdam, The Netherlands.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1996 May;81(5):607-12. doi: 10.1016/s1079-2104(96)80057-6.
The aim of this study was to determine the effect of dose reduction on the image quality of two sensor systems with automatic greyscale adjustment.
Two digital sensor systems, Sidexis (Siemens, Bensheim, Germany) and Digora (Soredex, Helsinki, Finland), were tested. The image quality of the systems was determined by comparing lengths of endodontic files (025, 020, 015, and 010 files) and a premolar root in the digital images with lengths on conventional radiographic films. For the experiments the exposure was changed to 100%, 50%, 25%, 12.5%, 6.25%, and 3.125% of that for Ektaspeed films.
The lengths of 025 and 020 files and the premolar root in the digital images were comparable with the lengths on films even if the exposure was reduced to 6% of that used for Ektaspeed films. The lengths of 015 files reduced as the exposure was reduced. The lengths of 010 files were significantly shorter than the lengths on films.
With the systems tested, a dose reduction of approximately 95% compared with Ektaspeed films is possible to determine the lengths of a premolar root and 025 and 020 files. For thinner objects a dose reduction is questionable.
本研究旨在确定剂量降低对两种具有自动灰度调整功能的传感器系统图像质量的影响。
对两种数字传感器系统进行了测试，分别是Sidexis（德国本斯海姆西门子公司）和Digora（芬兰赫尔辛基索雷德斯公司）。通过将数字图像中根管锉（025、020、015和010号锉）和一颗前磨牙牙根的长度与传统X线胶片上的长度进行比较，来确定系统的图像质量。在实验中，将曝光量改变为Ektaspeed胶片曝光量的100%、50%、25%、12.5%、6.25%和3.125%。
即使曝光量降低至Ektaspeed胶片所用曝光量的6%，数字图像中025和020号锉以及前磨牙牙根的长度仍与胶片上的长度相当。015号锉的长度随着曝光量的降低而缩短。010号锉的长度明显短于胶片上的长度。
对于所测试的系统，与Ektaspeed胶片相比，降低约95%的剂量仍有可能确定前磨牙牙根以及025和020号锉的长度。对于更细的物体，剂量降低是否可行值得怀疑。
