Hirschmann P N
Int Dent J. 1987 Mar;37(1):31-7.
The current status of dental panoramic tomography (rotational panoramic radiography) is reviewed. This technique is based on a combination of tomography and slit-beam radiography to provide an image of both jaws on a single film. There is a greater degree of image degradation when compared with conventional radiographic techniques due to tomographic blurring, magnification and distortion, secondary images and burn-out. Meticulous patient position is essential to accommodate their jaws to the image layer determined by the manufacturers. The absorbed doses from panoramic radiography are of a similar order to that from bitewing radiography and lower than those from a full-mouth periapical series. The individual risk of 1.3 X 10(-6) is compared with that from other radiographic examinations and smoking. The collective risk, 1.04 deaths in the UK in 1981, is relatively insignificant as is the genetic dose. The risk to the dentist and his staff is also low compared to other risks. The methods of dose limitation currently available are reviewed. The clinical indications are considered in relation to the guidelines of the American Dental Association and the Dental Estimates Board in the UK. The problems associated with attempts to measure diagnostic yield are considered. In view of the world-wide public concern at the potential dangers of ionising radiation, dentists are urged to maximize the diagnostic yield from their panoramic radiography by taking such radiographs only when clinically necessary, ensuring meticulous positioning and processing, followed by scrupulous assessment of the radiography for any sign of pathological change.
本文综述了牙科全景体层摄影术（旋转全景X线摄影）的现状。该技术基于体层摄影术和狭缝束X线摄影术的结合，可在一张胶片上提供上下颌的影像。与传统X线摄影技术相比，由于体层模糊、放大和畸变、二次影像及图像消蚀，图像退化程度更高。患者的精确体位对于使其颌骨适应制造商确定的影像层至关重要。全景X线摄影的吸收剂量与咬合翼片X线摄影的吸收剂量处于同一量级，且低于全口根尖片系列的吸收剂量。将个体风险1.3×10⁻⁶与其他X线检查及吸烟的风险进行了比较。1981年英国的集体风险为1.04例死亡，与遗传剂量一样相对微不足道。与其他风险相比，对牙医及其工作人员的风险也较低。本文综述了目前可用的剂量限制方法。结合美国牙科协会和英国牙科评估委员会的指南对临床适应证进行了考量。对与尝试测量诊断效率相关的问题进行了探讨。鉴于全球公众对电离辐射潜在危险的关注，敦促牙医仅在临床必要时拍摄全景X线片，确保精确的体位和冲洗，随后仔细评估X线片是否有任何病理变化迹象，从而使全景X线摄影的诊断效率最大化。
