Introduction:The proven radio sensitivity and the position of the thyroid gland make it a significant organ during the dental radiography exposure.Objectives:This study compared the surface radiation dose to the thyro...Introduction:The proven radio sensitivity and the position of the thyroid gland make it a significant organ during the dental radiography exposure.Objectives:This study compared the surface radiation dose to the thyroid gland region during two different techniques of two dimensional(2D)conventional orthopantomography(OPG)and three dimensional(3D)OPG reconstructed from cone beam computed tomography(CBCT).Methods:The entrance surface dose to the thyroid region of the patients was evaluated using a personal dosimeter in a sample of 156 patients who prescribed for an OPG examination.Results:The obtained mean dose values for conventional OPG and reconstructed OPG from CBCT are 7.47μSv and 28.65μSv,respectively.Further a significant difference(p<0.05)was observed between those two doses.Conclusions:A significant amount of dose reduction to the thyroid gland region can be obtained when using conventional OPG compared to the CBCT.展开更多
目的评价口腔颌面锥形束CT（codebeamCT，CBCT）确定下颌阻生第了磨牙（impacted mandibular third molar，IMTM）与下牙槽神经管位置关系，为IMTM拔除术中预防下牙槽神经损伤提供临床依据。方法通过IMTM拔除术前曲面体层x线片检查，筛...目的评价口腔颌面锥形束CT（codebeamCT，CBCT）确定下颌阻生第了磨牙（impacted mandibular third molar，IMTM）与下牙槽神经管位置关系，为IMTM拔除术中预防下牙槽神经损伤提供临床依据。方法通过IMTM拔除术前曲面体层x线片检查，筛选出IMTM与下牙槽神经管存在较大范嗣接触或部分重叠影像表现的49例患者（60侧），进一步行CBCT检查，结合种植机微动力系统微创拔牙术中观察结果，应用诊断试验的方法评价术前CBCT检佥结果的准确性。结果术前CBCT观察IMTM突破下牙槽神经管壁判断的灵敏度82．8％、特异度87．0％，Youden指数0．69，阳性预测值88．9％，阴性预测值80．0％。两位口腔放射医师术前对CBCT共同判读的结果与术中观察结果的符合率为84．6％（44／52）。对两位医师术前分别判读CBCT影像的结果进行一致性分析，Kappa值=0．80。结论对于曲面体层x线片显示IMTM与下牙槽神经管存在较大范围接触或部分重叠影像表现的病例应用CBCT术前检查，CBCT显示的IMTM与下牙槽神经管的关系与临床实际观察结果一致性较高。展开更多
文摘Introduction:The proven radio sensitivity and the position of the thyroid gland make it a significant organ during the dental radiography exposure.Objectives:This study compared the surface radiation dose to the thyroid gland region during two different techniques of two dimensional(2D)conventional orthopantomography(OPG)and three dimensional(3D)OPG reconstructed from cone beam computed tomography(CBCT).Methods:The entrance surface dose to the thyroid region of the patients was evaluated using a personal dosimeter in a sample of 156 patients who prescribed for an OPG examination.Results:The obtained mean dose values for conventional OPG and reconstructed OPG from CBCT are 7.47μSv and 28.65μSv,respectively.Further a significant difference(p<0.05)was observed between those two doses.Conclusions:A significant amount of dose reduction to the thyroid gland region can be obtained when using conventional OPG compared to the CBCT.
文摘目的评价口腔颌面锥形束CT（codebeamCT，CBCT）确定下颌阻生第了磨牙（impacted mandibular third molar，IMTM）与下牙槽神经管位置关系，为IMTM拔除术中预防下牙槽神经损伤提供临床依据。方法通过IMTM拔除术前曲面体层x线片检查，筛选出IMTM与下牙槽神经管存在较大范嗣接触或部分重叠影像表现的49例患者（60侧），进一步行CBCT检查，结合种植机微动力系统微创拔牙术中观察结果，应用诊断试验的方法评价术前CBCT检佥结果的准确性。结果术前CBCT观察IMTM突破下牙槽神经管壁判断的灵敏度82．8％、特异度87．0％，Youden指数0．69，阳性预测值88．9％，阴性预测值80．0％。两位口腔放射医师术前对CBCT共同判读的结果与术中观察结果的符合率为84．6％（44／52）。对两位医师术前分别判读CBCT影像的结果进行一致性分析，Kappa值=0．80。结论对于曲面体层x线片显示IMTM与下牙槽神经管存在较大范围接触或部分重叠影像表现的病例应用CBCT术前检查，CBCT显示的IMTM与下牙槽神经管的关系与临床实际观察结果一致性较高。
