J Korean Acad Conserv Dent.  2006 Sep;31(5):390-397. 10.5395/JKACD.2006.31.5.390.

In vitro evaluation of accuracy and consistency of four different electronic apex locators

• Cho JH
• Kum KY
• Lee SJ

• KMID: 1986882
• DOI: http://doi.org/10.5395/JKACD.2006.31.5.390

Abstract

The purpose of this study was to evaluate the accuracy and the consistency of four different electronic apex locators in an in vitro model. Fourty extracted premolars were used for the study. Four electronic apex locators (EAL) were Root ZX, SmarPex, Elements Diagnostic Unit (EDU), and E-Magic Finder Deluxe (EMF). After access preparation, the teeth were embedded in an alginate model and the length measurements were carried out at "0.5"and "Apex"mark using four EALs. The file was cemented at the location of the manufacturers'instruction (Root ZX, EDU, EMF: 0.5 mark, SmarPex: Apex mark). The apical 4mm of the apex was exposed and the distance from the file tip to the major foramen was measured by Image ProPlus (x 100). The distance from the file tip to the major foramen was calculated at 0.5 and Apex mark and the consistency of 0.5 and Apex mark was compared by SD and Quartile of Box plots. In this study, Root ZX and EMF located the apical constriction accurately within +/- 0.5 mm in 100%, whereas SmarPex and EDU located in 90% and in 70% respectively. For Root ZX and EMF, there was no significant difference between the consistency of 0.5 and Apex mark. However, for the EDU and SmarPex, Apex mark was more consistent than 0.5 mark. From the evaluation of the consistency in this study, for Root ZX and EMF, both 0.5 and Apex mark can be used as a standard mark. And for EDU and SmarPex, the Apex mark can be recommended to be used as a standard mark.

Keyword

Electronic apex locator; Consistency; Accuracy; Alginate model; Major foramen; Apical constriction

MeSH Terms

Bicuspid
Constriction
Tooth

Figure

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  Figure 1 Alginate model.

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  Figure 2 Length measurement with Digital caliper.

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  Figure 3 Distance measurement between the file tip and major foramen by Image ProPlus.

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  Figure 4 Box plots : Distance between the file tip and the major foramen at 0.5 and Apex mark (Quartile: the value of 75%-the value of 25%, The mark in which Quartile is smaller is more consistent).

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