Burger C L, Mork T O, Hutter J W, Nicoll B
Naval Dental Clinic, Great Lakes, IL, USA.
J Endod. 1999 Apr;25(4):260-3. doi: 10.1016/S0099-2399(99)80155-1.
A recent development in direct digital radiography (DDR) has made it possible to make additive multiple point (click) measurements of onscreen images. Canal length was examined using four estimation methods: measurement of a conventional D-speed film radiograph, and onscreen DDR allowing two clicks, six clicks, and an unlimited number of clicks of the measuring device. Thirty extracted human teeth with root curvatures ranging from 7 degrees to 47 degrees (Schneider method) were examined. Actual canal length was measured using a millimeter rule and x 2 magnification. Teeth were mounted and prepared for conventional and DDR imaging. Estimated canal length was determined by three board-certified endodontists using each of the four techniques. A two-way analysis of variance indicated that all radiographic techniques resulted in canal lengths that were significantly different from the true canal length, and there was no significant difference between experimental groups, regardless of the canal curvature.
直接数字射线照相术（DDR）的一项最新进展使得对屏幕图像进行附加多点（点击）测量成为可能。使用四种估计方法检查根管长度：测量传统D速胶片射线照片，以及在屏幕上进行DDR测量，测量设备分别允许两次点击、六次点击和无限次点击。检查了30颗拔除的人牙，其牙根弯曲度范围为7度至47度（施奈德法）。使用毫米尺和2倍放大率测量实际根管长度。将牙齿安装并准备进行传统和DDR成像。由三位获得委员会认证的牙髓病医生使用四种技术中的每一种来确定估计的根管长度。双向方差分析表明，所有射线照相技术得出的根管长度均与真实根管长度存在显著差异，并且无论根管弯曲度如何，实验组之间均无显著差异。
