低剂量技术在儿童埋伏牙口腔全景摄影中的应用

Application of Low Dose Technology in Dental Panoramic Radiography of Children Impacted Teeth

目的探讨儿童埋伏牙口腔全景摄影时的低剂量摄影技术。方法 120例患儿采用儿童模式P10,以12岁为界,随机分成常规组(>12岁)、常规组(≤12岁)、低剂量组(>12岁)及低剂量组(≤12岁)四组即A、B、C、D组,每组30例。常规组、C组及D组分别采用62 kV、8 mA,60 kV、6 mA及60 kV、5 mA进行曝光,记录每次的曝光条件、剂量面积乘积(DAP)值和有效剂量(ED)。由两名主任医师按5级评分法对图像诊断接受率及主观噪声进行评分。结果四组图像均能准确显示埋伏牙结构及其周边关系。与常规组相比,剂量方面低剂量组(>12岁)下降28.6%,低剂量组(≤12岁)下降40.5%;质量方面低剂量组的图像诊断接受率和主观噪声评分较低,但仍能满足埋伏牙的诊断要求。结论埋伏牙患儿口腔全景摄影时,12岁以上及以下分别采用60 kV、6 mA及60 kV、5mA的曝光条件,可以实现低剂量摄影。

Objective To investigate the low dose technology in dental panoramic radiography of children impacted teeth. Methods 120 children received the DR panoramic radiography mode suited for children（P10） and were bounded by 12 years old, 120 children were randomly divided into four groups, include the conventional group（ 〉 12y）, the conven- tional group（ ~12y）, low dose group（ 〉 12y） and low dose group（~〈12y） called A, B, C and D group,and each group included 30 cases. The conventional group, C group and D group were exposed in the appropriate mode,which tube voltage was respectively 62, 60 and 60 and which tube current was respectively 8mA, 6mA and 5mA, and exposure conditions, DAP values and effective doses （ED）were recorded. The acceptance rate of diagnostic imaging and the subjective noise was scored by two chief physicians with the score of 5 levels. Results The images in with PIO mode were accurately depicted the impacted teeth structures and the surrounding ralationship. Compared with the conventional groups, the low dose group （ 〉 12y） declined by 28.6 percent and the low dose group（~12y） declined 40.5 percent in dosage,the scores of the ac- ceptance rate of diagnostic imaging and the subjective noise were relatively low in the low dose groups, however, the images could still be satisfied on the diagnostic requirements of impacted teeth. Conclusion The low dose photography could be used in the dental panoramic radiography of children impacted teeth with 60K, 6mA for the children more than 12 years old and 60KV, 5mA for the children below 12 years old.