The development of the portable x-ray equipment for dentistry.

本研究的目的是建立一种安全、实用的家庭牙科X线检查方法。为了减少患者、牙医和辅助人员的剂量，研制了一种便携式X射线设备，该设备使用X射线CCD传感器。采用透明防护材料KYOWAGLAS-XA研制了便携式X射线机照射锥防护罩。它可以从病人的散射X射线阴影。将照射锥更换为透明材料，使X线投照定位容易、安全。研制了X射线CCD传感器的保持装置。它由两个可伸缩的臂和安装装置组装而成。使用该夹持装置，可以在不需要任何辅助人员的情况下，准确、安全地进行X线检查。使用该便携式X射线设备，在距离患者1 m处，牙科医生的最大剂量为3.12μSv/sec（0.936μSv/次检查）。按15000个齿距病人20 cm照射计算，牙医年最大剂量估计为6.75mSv。协助人员或家属在防护罩后50次照射，距患者1 m处年最大剂量为0.9μSv。作为一个未来的主题，似乎减少X射线头的重量是必要的便携性。

The purpose of this research is to establish an X-ray examination which is safe and useful for the home dental treatment. A portable X-ray equipment was developed in order to reduce the dose of patients, dentists and assistant persons using a X-ray CCD sensor. A protection shade attached to the irradiation cone of the portable X-ray equipment was developed with clear protection material such as KYOWAGLAS-XA. It could shade from the scattered X-rays of the patient. The irradiation cone was changed to a clear material one so that the positioning of X-ray projection was accomplished easily and safely. A hold device of the X-ray CCD sensor was also developed. It was assembled with two extensible arms and mounting devices. Using this hold device, the X-ray examination could be performed accurately and safely without any dose of assistant person . The maximum dose of dentist was 3.12μSv/sec (0.936μSv/examination) at the distance of 1m from the patient using this portable X-ray equipment. The maximum estimated dose of dentist was 6.75mSv a year by the exposure of 15, 000 tines at the distance of 20cm from the patient. The maximum dose of assistant person or family was 0.9μSv at the distance of 1 m from patient a year by the exposure of 50 times behind the protection shade. As a future subject it seemed that the reduction of the weight of the X-ray head is necessary for the portability.