Hayakawa Y, Shibuya H, Ota Y, Kuroyanagi K
Department of Oral and Maxillofacial Radiology, Tokyo Dental College, Chiba, Japan.
Bull Tokyo Dent Coll. 1997 Feb;38(1):21-5.
This report describes the radiation dosage reduction possible in the general dental practice with two CCD (charge-coupled device)-based intraoral radiographic systems: the RVG-S (Trophy Radiologie, Vincennes, France) and the Sens-A-Ray (Regam Medical Systems, Sundsvall, Sweden). Radiation dosages (air-kerma; Gy) necessary for obtaining clinically acceptable images were measured at the cone tip using an ionization chamber type 660-1 (Nuclear Associates, Victoreen, Inc., Carle Place, New York, USA). When the RVG-S was used with an Oramatic 70 (Trophy Radiologie) X-ray generator, dosages at the cone tip ranged from 322 to 612 microGy. These corresponded to 40-60% of the dosages necessary when using Ektaspeed dental X-ray film (Eastman Kodak, Rochester, New York, USA) with a Heliodent 70 (Siemens, Erlangen, Germany) X-ray generator. At 60 kVp, the Sens-A-Ray reduced the dosage in the order of 30% compared with Ektaspeed dental X-ray film. Reduction in radiation dosage is one of the benefits of digital intraoral radiographic systems in general dental clinics. The RVG-S provides greater dose savings than does the Sens-A-Ray.
本报告描述了在一般牙科诊疗中，使用两种基于电荷耦合器件（CCD）的口腔内射线照相系统——RVG-S（法国万森纳 Trophy Radiologie 公司）和 Sens-A-Ray（瑞典松兹瓦尔 Regam Medical Systems 公司），可实现的辐射剂量降低情况。使用型号为 660-1 的电离室（美国纽约卡尔普莱斯维克托林公司 Nuclear Associates 生产）在锥尖处测量获得临床可接受图像所需的辐射剂量（空气比释动能；Gy）。当 RVG-S 与 Oramatic 70（Trophy Radiologie）X 射线发生器配合使用时，锥尖处的剂量范围为 322 至 612 微戈瑞。这些剂量相当于使用美国纽约罗切斯特伊士曼柯达公司的 Ektaspeed 牙科 X 光胶片与德国埃尔朗根西门子公司的 Heliodent 70 X 射线发生器配合使用时所需剂量的 40%至 60%。在 60 kVp 时，与 Ektaspeed 牙科 X 光胶片相比，Sens-A-Ray 的剂量降低了约 30%。一般牙科诊所中，降低辐射剂量是数字口腔内射线照相系统的优势之一。RVG-S 比 Sens-A-Ray 节省的剂量更多。
