ElAyouti A, Kimionis I, Chu A-L, Löst C
Department of Conservative Dentistry and Endodontology, University of Tübingen, Tübingen, Germany.
Int Endod J. 2005 Nov;38(11):827-33. doi: 10.1111/j.1365-2591.2005.01024.x.
To assess ex vivo the accuracy of various electronic apex locators in locating the apical terminus of root-end resected teeth.
Ninety extracted human posterior teeth (182 root canals) were prepared to a minimum size of 40 and filled with gutta-percha and sealer. After resection of the apical 3 mm of the root, the root canal filling was removed using HERO rotary instruments. The size of the root canal at the apical terminus after removal of the filling ranged from size 50 to 90. The root canal length to the apical terminus was determined using 3 apex locators (Root ZX, Raypex4 and Apex Pointer). A new mounting model that utilized a micrometer was used to perform the measurements and to visually determine the actual position of the apical terminus. The frequency of locating the apical terminus and the corresponding 95% confidence interval (CI) were calculated. Additionally, the coefficient of repeatability of each apex locator and the limits of inter-operator agreement were determined.
All apex locators showed an acceptable repeatability (0.02-0.03 mm coefficient of repeatability) and narrow limits of inter-operator agreement (+0.07 and -0.07 mm). The accuracy of determining the apical terminus within 1 mm in the root canal was as follows: Root ZX 90% (164/182 root-canals) [95%CI: 86-94%], Raypex4 74% (135/182 root-canals) [95%CI: 68-80%], and Apex Pointer 71% (129/182 root canals) [95%CI: 65-77%]. No over-instrumentation resulted when the Root ZX device was used. In contrast, using the Raypex4 or the Apex Pointer device resulted in over-instrumentation in 8 of 182 root canals (4%).
Under the conditions of this study all three apex locators were able to detect the apical terminus of root-end resected teeth with an acceptable range. The Root ZX device was the most accurate without over-instrumentation of the root canals.
在体外评估各种电子根尖定位仪在确定根尖切除后牙齿根尖终点位置时的准确性。
选取90颗拔除的人类后牙（182个根管），预备至最小尺寸40号，并用牙胶和封闭剂充填。在根尖切除3mm后，使用HERO旋转器械去除根管充填物。去除充填物后根尖终点处根管的尺寸范围为50号至90号。使用3种根尖定位仪（Root ZX、Raypex4和Apex Pointer）确定至根尖终点的根管长度。采用一种利用千分尺的新型安装模型进行测量，并直观确定根尖终点的实际位置。计算确定根尖终点的频率及相应的95%置信区间（CI）。此外，还确定了每种根尖定位仪的重复性系数及操作者间的一致性界限。
所有根尖定位仪均显示出可接受的重复性（重复性系数为0.02 - 0.03mm）和较窄的操作者间一致性界限（+0.07和 - 0.07mm）。在根管内1mm范围内确定根尖终点的准确性如下：Root ZX为90%（164/182个根管）[95%CI：86 - 94%]，Raypex4为74%（135/182个根管）[95%CI：68 - 80%]，Apex Pointer为71%（129/182个根管）[95%CI：65 - 77%]。使用Root ZX设备时未出现过度预备情况。相比之下，使用Raypex4或Apex Pointer设备时，182个根管中有8个（4%）出现了过度预备。
在本研究条件下，所有三种根尖定位仪均能在可接受范围内检测到根尖切除后牙齿的根尖终点。Root ZX设备最为准确，且不会对根管进行过度预备。
