Influence of embedding media on the accuracy of working length determination by means of apex locator: an ex vivo study

AbstractThe aim of this research was to determine ex vivo the influence on accuracy of five different embedding media, for investigative and educational purposes, and one electronic apex locator. 110 human extracted mature roots of permanent single-rooted human teeth were used. The roots were embedded in alginate, stick sponge, 2% agar–agar and 6% and 12% gelatin. The actual working length to the physiological foramen was determined under a stereo-microscope (16 ×) and the electronic working lengths with the Elements Diagnostic Unit and a K-file ISO 10. The accuracy ranges of the accumulated measurements, when allowing a ± 0.5 mm tolerance, went from 98.2% (6% and 12% gelatin), 93.7% (alginate), 92.8% (2% agar–agar) to 91.7% (sponge). The exact measurements at the physiological foramen ranged from 80.0% (6% gelatin), 76.5% (2% agar–agar), 71.8% (12% gelatin), 68.2% (alginate) to 64.5% (sponge). Although relatively seldom (n = 24), measurements with deviations of more than ± 0.5 mm were also observed; thus, the accuracy of the working length determination results per se can be considered as clinically acceptable. The results of this research allow a recommendation of the investigated embedding media for electronic working length determination models for educational and research purposes in endodontics.

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Accuracy of Working Length Determination using NovApex and Root-ZX Apex Locators: An in vitro Study

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-2051 ◽

2017 ◽

Vol 18 (5) ◽

pp. 383-385 ◽

Cited By ~ 1

Author(s):

Vahid Zand ◽

Saeed Rahimi ◽

Paria Davoudi ◽

Abubakr Afshang

Keyword(s):

Ex Vivo ◽

In Vitro Study ◽

High Accuracy ◽

Human Teeth ◽

Visual Technique ◽

Working Length ◽

Significant Difference ◽

Length Determination ◽

Electronic Apex Locator

ABSTRACT Introduction This ex vivo study evaluated the accuracy of the Root-ZX electronic apex locator (EAL) (J. Morita, Tokyo, Japan) and the NovApex (Forum Technologies, Rishon Lezion, Israel) in determining the working length (WL) during endodontic treatment. Materials and methods Forty extracted single-rooted human teeth were selected for this study. The actual WL was measured with visual technique by a size #15 k-file under magnification. Then, the canal lengths were measured electronically with both Root-ZX and NovApex apex locators within ±0.5 and ±1 mm. Mean percentage of data was analyzed between groups using paired t-test, with a statistically significant level of p < 0.05. Results The accuracy of NovApex apex locator was 85% within ±0.5 mm and 92.5% within ±1 mm. The accuracy of Root-ZX apex locator was 70% within ±0.5 mm and 97.5% within ±1 mm. There was no significant difference between the accuracy of the two EALs. Conclusion Both the NovApex and Root-ZX EALs are useful for measuring the WL with high accuracy. Clinical significance Given the importance of accurate WL determination in the success of endodontic treatments, the accuracy of different apex locators should be evaluated. How to cite this article Zand V, Rahimi S, Davoudi P, Afshang A. Accuracy of Working Length Determination using NovApex and Root-ZX Apex Locators: An in vitro Study. J Contemp Dent Pract 2017;18(5):383-385.

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Correlation of objective image quality and working length measurements in different CBCT machines: An ex vivo study

Scientific Reports ◽

10.1038/s41598-020-76424-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

T. G. Wolf ◽

F. Fischer ◽

R. K. W. Schulze

Keyword(s):

Image Quality ◽

Ex Vivo ◽

Quality Factors ◽

Study Objective ◽

Intra Class Correlation ◽

Working Length ◽

Length Determination ◽

Image Quality Measures ◽

Operator Reproducibility ◽

Ex Vivo Study

Abstract To investigate potential correlations between objective CBCT image parameters and accuracy in endodontic working length determination ex vivo. Contrast-to-noise ratio (CNR) and spatial resolution (SR) as fundamental objective image parameters were examined using specific phantoms in seven different CBCT machines. Seven experienced observers were instructed and calibrated. The order of the CBCTs was randomized for each observer and observation. To assess intra-operator reproducibility, the procedure was repeated within six weeks with a randomized order of CBCT images. Multivariate analysis (MANOVA) did not reveal any influence of the combined image quality factors CNR and SR on measurement accuracy. Inter-operator reproducibility as assessed between the two observations was poor, with a mean intra-class correlation (ICC) of 0.48 (95%-CI 0.38, 0.59) for observation No. 1. and 0.40 (95%-CI 0.30, 0.51) for observation No. 2. Intra-operator reproducibility pooled over all observers between both observations was only moderate, with a mean ICC of 0.58 (95%-CI 0.52 to 0.64). Within the limitations of the study, objective image quality measures and exposure parameters seem not to have a significant influence on accuracy in determining endodontic root canal lengths in CBCT scans. The main factor of variance is the observer.

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Accuracy of Working Length Measured by Apex Locator and Digital Radiography

Journal of The Pakistan Dental Association ◽

10.25301/jpda.301.24 ◽

2021 ◽

Vol 30 (1) ◽

pp. 24-28

Author(s):

Ghulam Ishaq Khan ◽

◽

Muhammad Talha Khan ◽

Saroosh Ehsan ◽

Anam Fayyaz ◽

...

Keyword(s):

Digital Radiography ◽

Root Canal ◽

Reference Points ◽

Radiographic Measurement ◽

Apical Constriction ◽

Actual Length ◽

Actual Working ◽

Working Length ◽

Length Determination ◽

Electronic Apex Locator

OBJECTIVE: The objective of this study was to compare the measurements of electronic and radiographic method of working lengths calculation with actual working length of root canals. Precise working length determination is the most important part for successful root canal procedure. The most commonly used methods to determine the working length in root canal treatment are radiography and electronic apex locator. METHODOLOGY: A cross sectional study was done over a period of 06 months in the Department of Operative Dentistry, Fatima Memorial Hospital, Lahore. Sixty patients who were recommended extraction of their premolar teeth with sixty canals were selected by convenience sampling. The Root ZX* apex locator was used to determine electronic working length exactly identifying the apical constriction. Reference points were identified and radiographic working length were determined 1mm short of radiographic apex. The teeth were extracted along with file cemented before extraction inside root canal. The actual length of the root canal was then calculated using the same files and reference point with 3.5X magnification. Pearson chi square test was applied to compare the apex locator and digital radiographic measurement with actual working length. RESULTS: The Root ZX® apex locator was 95% accurate to identify the apical constriction as compared 70% accuracy given by radiographs within 0.5 mm of the apex. CONCLUSION: Electronic apex locator was more accurate as compared to digital radiography in working length determination. KEYWORDS: Working length (WL), Electronic apex locators (EAL), Radiographic working length(RWL), Apical constriction (AC) HOW TO CITE: Khan GI, Khan MT, Ehsan S, Fayyaz A, Malik HA, Hussain S. Accuracy of working length measured by apex locator and digital radiography. J Pak Dent Assoc 2021;30(1):24-28.

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Clinical Accuracy of Electronic Apex Locator in Measuring Working Length during Root Canal Treatment

Bangladesh Medical Research Council Bulletin ◽

10.3329/bmrcb.v43i3.36411 ◽

2018 ◽

Vol 43 (3) ◽

pp. 120-125

Author(s):

AKM Bashar ◽

Tanzila Rafique ◽

Ranjit Ghosh ◽

Kamal Abdullah ◽

Mohmood Sajedeen ◽

...

Keyword(s):

Root Canal ◽

Ex Vivo ◽

Pearson Correlation ◽

Root Canal Treatment ◽

Acceptable Range ◽

Actual Working ◽

Working Length ◽

Clinical Accuracy ◽

Electronic Apex Locator

Obtaining a correct working length is critical to success of endodontic therapy. The procedure for establishment of working length should be performed using techniques that have been proven to give valuable and accurate results and methods that are practical and efficacious. The development of the electronic apex locator has helped to assess the working length more accurate and predictable. So the objective of this in vivo-ex vivo study was to evaluate the clinical accuracy of electronic apex locator in measuring the working length of the root canal in vivo, and comparing the lengths so measured, to the actual working length, ex vivo and after extraction. Electronic apex locator C-Root-I VI (Foshan COXO Medical Instrument Co. China) was used to measure the working length in 100 root canals (one palatal canal and one buccal canal in fifty maxillary 1st premolar) in vivo before extraction, that were scheduled for orthodontic treatment in twenty-five patients. Teeth were then extracted and apical constrictions were identified by careful preparation of the apical 4 mm of all the roots. Actual working lengths were determined by adjusting an endodontic file in the root canal upto the constriction from the coronal reference point. Electronic working lengths obtained in vivo were then compared for coincidence with the actual lengths thus measured after extraction (ex vivo). The data were statistically analysed by a paired Student 't' test and Pearson correlation-coefficient test. In 14 canals out of 100 electronic working lengths (EWL) truly coincided with actual working length (AWL). Eighty two canals out of 100, EWLs were <0.5 mm short in measurement than AWLs but the difference with AWL was statistically insignificant (p >0.01). Only in 4 canals (4%) EWLs were either >0.5mm short or more than AWL, thereby fail to meet the criteria of acceptable range of coincidence (⩽0.5 mm from the apical constriction). On reliability analysis, all (100%) electronic working length significantly correlate with the actual working length (r=0.971). Within a clinically acceptable range of ⩽0.5 mm, C Root I apex locator device showed a high degree of success (96%) in determination of working length during root canal treatment.

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Comparison of working length determination using apex locator and manual method - ex vivo study

Dentistry and Medical Research ◽

10.4103/2348-1471.184730 ◽

2016 ◽

Vol 4 (2) ◽

pp. 39

Author(s):

Lucasda Fonseca Roberti Garcia ◽

JhadyeAlves Carneiro ◽

FredsonMarcio Acris de Carvalho ◽

AndreAugusto Franco Marques ◽

EmilioCarlos Sponchiado Junior ◽

...

Keyword(s):

Ex Vivo ◽

Manual Method ◽

Working Length ◽

Length Determination ◽

Ex Vivo Study

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Comparison of Five different methods of Working length determination: An ex vivo study

Endodontology ◽

10.4103/endo.endo_30_20 ◽

2020 ◽

Vol 32 (4) ◽

pp. 187

Author(s):

PalaniSelvi Kamaraj ◽

Hemalatha Parandhaman ◽

Vidhya Raguganesh

Keyword(s):

Ex Vivo ◽

Working Length ◽

Length Determination ◽

Ex Vivo Study

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Comparative Study of Periapical Radiographic Techniques with Apex Locator for Endodontic Working Length Estimation: An ex vivo Study

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1022 ◽

2011 ◽

Vol 12 (2) ◽

pp. 131-134 ◽

Cited By ~ 1

Author(s):

Vaishali Parekh ◽

Chirag Taluja

Keyword(s):

Comparative Study ◽

Ex Vivo ◽

Mean Value ◽

Length Estimation ◽

Radiographic Technique ◽

Working Length ◽

Significant Difference ◽

Length Determination ◽

Ex Vivo Study

ABSTRACT Background Accurate assessment of working length determines the success and prognosis of an endodontic treatment outcome. Various methods are used in determining the working length. Aim Compare the measurements of the apex locator and radiographic technique to determine working length. Methods An ex vivo study was conducted on 20 patients having intact single straight root canal. Only premolars were taken in the study. After doing coronal flaring and irrigation, the radiographic length was determined with an aid of a k-type file and electronic length (EL-Root-ZX) 3rd generation apex locator. After extraction of all the premolars, stereomicroscope was further used to confirm and compare radiographic and electronic apex locator. Results A mean value of 0.5430 ± 0.5741 mm was observed among radiographic techniques. A mean value of 0.4240 ± 0.4587 mm was observed among apex locator techniques. Ttest revealed, no significant difference between the two techniques was observed (p = 0. 615). ‘Two tailed’ t-test revealed intragroup significance both techniques for determining the working length. Conclusion The distance of the apical foramen to the tip of the file: A mean value of 0.4240 ± 0.4587 mm with apex locator technique was observed. Working length of apex locator was more in comparison to radiographic technique. No significant difference between the two techniques was observed (p = 0. 615). Intragroup significance among both techniques for determining the working length was also observed. However, a further study incorporating a larger sample size and utilization of both techniques of working length determination on the same tooth has to be conducted. Clinical significance Combining the apex locator technique and radiographic technique for determination of working length would yield more accurate working length. How to cite this article Parekh V, Taluja C. Comparative Study of Periapical Radiographic Techniques with Apex Locator for Endodontic Working Length Estimation: An ex vivo Study. J Contemp Dent Pract 2011;12(2):131-134.

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Root Canal Penetration of a Sodium Hypochlorite Mixture Using Sonic or Ultrasonic Activation

Brazilian Dental Journal ◽

10.1590/0103-6440201300209 ◽

2014 ◽

Vol 25 (6) ◽

pp. 489-493 ◽

Cited By ~ 9

Author(s):

Marta Sáinz-Pardo ◽

Roberto Estevez ◽

Óliver Valencia de Pablo ◽

Giampiero Rossi-Fedele ◽

Rafael Cisneros

Keyword(s):

Sodium Hypochlorite ◽

Root Canal ◽

Ex Vivo ◽

Positive Pressure ◽

Ultrasonic Activation ◽

Penetration Length ◽

Working Length ◽

Closed Systems ◽

Canal Shaping ◽

Ex Vivo Study

The purpose of this ex vivo study was to determine, in "open" and "closed" systems, whether the design has an influence on the penetration length of sodium hypochlorite mixed with a radiopaque contrast medium, measured in millimeters, when delivered using positive pressure (PP) and using sonic (SI) or passive ultrasonic (PUI) activation. Sixty single-rooted teeth were divided into two groups: open and closed systems (n=30). Root canal shaping was performed to a working length of 17 mm. The samples were divided into three sub-groups (n=10) according to irrigant delivery and activation: PP, and SI or PUI activation. By using radiographs, penetration length was measured, and vapor lock was assessed. For the closed group, the penetration distance means were: PP 15.715 (±0.898) mm, SI 16.299 (±0.738) mm and PUI 16.813 (±0.465) mm, with vapor lock occurring in 53.3% of the specimens. In the open group, penetration to 17 mm occurred in 97.6% of the samples, and no vapor lock occurred. Irrigant penetration and distribution evaluation using open and closed systems provide significantly different results. For closed systems, PUI is the most effective in delivering the irrigant to working length, followed by SI.

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An in vivo Evaluation of Different Methods of Working Length Determination

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1378 ◽

2013 ◽

Vol 14 (4) ◽

pp. 644-648 ◽

Cited By ~ 4

Author(s):

Nitin Shah ◽

Sarita Singh ◽

Jyoti Mandlik ◽

Kalpana Pawar ◽

Paras Gupta ◽

...

Keyword(s):

Tactile Sensation ◽

Pulp Chamber ◽

In Vivo Evaluation ◽

Extraction Working ◽

Apical Constriction ◽

Working Length ◽

Length Measurements ◽

Length Determination ◽

Electronic Apex Locator

ABSTRACT Objective The purpose of this in vivo study was to compare the ability of digital tactile, digital radiographic and electronic methods to determine reliability in locating the apical constriction. Materials and methods Informed consent was obtained from patients scheduled for orthodontic extraction. The teeth were anesthetized, isolated and accessed. The canals were negotiated, pulp chamber and canals were irrigated and pulp was extirpated. The working length was then evaluated for each canal by digital tactile sensation, an electronic apex locator (The Root ZX) and digital radiography. The readings were then compared with post-extraction working length measurements. Results The percentage accuracy indicated that EAL method (Root ZX) shows maximum accuracy, i.e. 99.85% and digital tactile and digital radiographic method (DDR) showed 98.20 and 97.90% accuracy respectively. Clinical significance Hence, it can be concluded that the EAL method (Root ZX) produced most reliable results for determining the accurate working length. How to cite this article Mandlik J, Shah N, Pawar K, Gupta P, Singh S, Shaik SA. An in vivo Evaluation of Different Methods of Working Length Determination. J Contemp Dent Pract 2013;14(4):644-648.

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