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

Article information

Restor Dent Endod. 2006;31(5):390-397
Publication date (electronic) : 2006 September 30
doi : https://doi.org/10.5395/JKACD.2006.31.5.390
1Department of Conservative Dentistry, Oral Science Research Center, Yonsei University, Seoul, Korea.
2Department of Conservative Dentistry, Dental Research Institute, Seoul National University, Seoul, Korea.
Corresponding Author: Seung-Jong Lee. Department of Conservative Dentistry, College of Dentistry, Yonsei University, 134, Shinchon-dong, Seodaemun-gu, Seoul, 120-752, Korea. Tel: 82-2-2228-8700, Fax: 82-2-313-7575, sjlee@yumc.yonsei.ac.kr
Received 2006 July 21; Revised 2006 August 15; Accepted 2006 September 08.

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 (× 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.

References

1. Grove C. Why canals should be filled to the dentinocemental junction. J Am Dent Assoc 1930. 17293–296.
2. Ricucci D, Langeland K. Apical limit of root canal instrumentation and obturation. Int Endod J 1998. 31394–409.
3. Suzuki K. Experimental study on iontophoresis. Jpn J Stomatol 1942. 16411–429.
4. Sunada I. New method for the measuring the length of the root canal. J Dent Res 1962. 41375–387.
5. Ushiyama J. New Principle and method for measuring the root canal length. J Endod 1983. 997–104.
6. Hasegawa K, Iizuka H, Takei M, Goto N, Nihei M, Ohashi M. A new method and apparatus for measuring root canal length. J Nihon Univ Sch Dent 1986. 28117–128.
7. Frank AL, Torabinejad M. An in vivo evaluation of Endex electronic apex locator. J Endod 1993. 19177–179.
8. Kobayashi C, Okiji T, Kaqwashima N, Suda H, Sunada I. A basic study on the electronic root canal length measurement: Part 3. Newly designed electronic root canal length measuring device using division method. Jpn J Conserv Dent 1991. 341442–1448.
9. Kobayashi C, Suda H. New electronic canal measuring device based on the ratio method. J Endod 1994. 20111–114.
10. Kobayashi C. Electronic canal length measurement. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1995. 79226–231.
11. Shabahang S, Goon WW, Gluskin AH. An in vivo evaluation of Root ZX electronic apex locator. J Endod 1996. 22616–618.
12. Dunlap CA, Remeikis NA, BeGole EA, Rauschenberger CR. An in vivo evaluation of an electronic apex locator that uses the ratio method. J Endod 1998. 2448–50.
13. Welk AR, Baumgartner JC, Marshall JG. An in vivo comparison of two frequency-based electronic apex locator. J Endod 2003. 29497–500.
14. Meares WA, Steiman HR. The influence of sodium hypochlorite irrigation on the accuracy of the Root ZX electronic apex locator. J Endod 2002. 28595–598.
15. Jenkins JA, Walker WA 3rd, Schindler WG, Flores CM. An in vitro evaluation of the accuracy of the Root ZX in the presence of various irrigants. J Endod 2001. 27209–211.
16. Lee SJ, Nam KC, Kim YJ, Kim DW. Clinical accuracy of a new apex locator with an automatic compensation circuit. J Endod 2002. 28706–709.
17. Kaufman AY, Keila S, Yoshpe M. Accuracy of a new apex locator: an in vitro study. Int Endod J 2002. 35186–192.
18. Kuttler Y. Microscopic investigation of root apexes. J Am Dent Assoc 1955. 50544–552.
19. Dummer PM, McGinn JH, Rees DG. The position and topography of the apical canal constriction and apical foramen. Int Endod J 1984. 17192–198.
20. Mayeda DL, Simon JH, Aimar DF, Finley K. In vivo measurement accuracy in vital and necrotic canals with the Endex apex locator. J Endod 1993. 19545–548.

Article information Continued

Figure 1

Alginate model.

Figure 2

Length measurement with Digital caliper.

Figure 3

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

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).

Table 1

Distance between the file tip and the major foramen measured by Image ProPlus (mm)

Table 1

Table 2

Distance between the file tip and the major foramen at 0.5 and Apex mark (mm)

Table 2