Czerw R J, Fulkerson M S, Donnelly J C, Walmann J O
U.S. Army Dental Activity, Texas 76544, USA.
J Endod. 1995 Nov;21(11):572-5. doi: 10.1016/S0099-2399(06)80988-X.
This study describes two tests of the in vitro accuracy of several models of electronic canal length measuring devices (ECLMDs) using a gelatin test model and extracted human teeth with fully formed apices. In part 1, four previously untested ECLMDs were used in dry canals after access and pulpectomy. File lengths with wth file tip just visible at the foramen were compared to ECLMD lengths. Clinically significant ECLMD measurements of > or + 0.5 mm than visual length were noted with two ECLMDs 16.6% and 10% of the time. The other two ECLMDs had no measurements >0.5 mm than the visual measurement. The gelatin test model proved highly accurate with 4 of 6 ECLMDs tested thus far. Part 2 compared the accuracy of a previously tested ECLMD using the gelatin model when taking length measurements with canals both dry and wet with distilled water in them. There was no difference between measurements in wet or dry canals. Irrigation with distilled water may be a clinical aid when using resistance ECLMDs.
本研究描述了使用明胶测试模型和具有完全形成根尖的拔除人类牙齿，对几种型号的电子根管长度测量仪（ECLMDs）进行体外准确性测试的两项试验。在第1部分中，在开髓和牙髓摘除术后，在干燥根管中使用了四种之前未测试过的ECLMDs。将锉尖在根尖孔刚可见时的锉长度与ECLMD测量长度进行比较。两种ECLMDs在16.6%和10%的时间里，其测量结果比视觉长度长或正0.5毫米，具有临床显著差异。另外两种ECLMDs没有测量结果比视觉测量长超过0.5毫米。到目前为止，在测试的6种ECLMDs中，有4种在明胶测试模型中表现出高度准确性。第2部分比较了一种之前测试过的ECLMD在使用明胶模型对干燥根管和充满蒸馏水的湿根管进行长度测量时的准确性。湿根管和干根管的测量结果没有差异。在使用电阻式ECLMDs时，用蒸馏水冲洗可能是一种临床辅助手段。
