In vitro evaluation of Root ZX and Raypex 6 in teeth with different apical diameters

Alameer S, Aldossary A, Almutairi W, N. Almaliki M, A. Farooqi F, Taymour N. The Effect of Coronal Pre-flaring and Type of Root Canal Irrigation on Working Length Accuracy Using Electronic Apex Locators

Background: Successful root canal treatment is influenced by the apical extent of root canal preparation and the eventual root canal filling. Achieving the full working length until the apical constriction, which is usually 0.5 - 1 mm shorter than the anatomical apex, is crucial. Electronic apex locators were used to detect the working length more accurately. There are six generations of electronic apex locators in the market. The selection of the appropriate irrigation with each apex locator for accurate working length determination is not fully investigated. Methods: The actual working lengths of 120 freshly extracted human single-rooted teeth were measured and compared with their working lengths using 3 rd generation (Root ZX) followed by 6 th generation (Raypex 6) apex locators in dry medium, presence of 5.25% sodium hypochlorite, and 2% chlorhexidine, without coronal pre-flaring and after coronal pre-flaring using the same irrigating media. Data were collected, tabulated, and afterward analyzed using one-way ANOVA with post-hoc to evaluate the significant difference in average working length between actual working length, Root ZX, and Raypex 6 apex locator working lengths accuracy. Results: The significant results were shown in roots that were coronally pre-flared and their working lengths were measured in a dry medium using Raypex 6 apex locator. While using the Root ZX apex locator, the most accurate results were shown in roots that were coronally pre-flared and their working lengths were measured while using a chlorhexidine irrigating solution. Conclusions: It is concluded that it is very important to know the specific irrigating medium to be used with each specific electronic apex locator to achieve the most accurate working length results.

Accuracy of Root ZX Electronic Apex Locator in Relation to Two Different Employment Protocols: An In Vitro Study

Objective The aim of this study is to determine the apical level of the root canal, whether it is the apical foramen or a level coronal to it, that Root ZX (J. Morita Co., Kyoto, Japan) targets and to identify its employment protocol that provides better accuracy. Methods Actual lengths (ALs) of 75 extracted single-rooted teeth were obtained by inserting a K-file size 8 until its tip was in level with the most coronal border of the apical foramen. Reference length (RL) was calculated by deducting 0.5 mm from AL. Roots were placed in porous sponge block soaked with Ringer's solution, and canals were irrigated with 2 mL of 5% sodium hypochlorite. The blinded operator used Root ZX to measure lengths with K-file size 8. In the first tested employment protocol, the file was advanced to the "APEX mark" of the digital display, and the length was obtained. The second employment protocol followed the manufacturer's recommendations by inserting the file until the "APEX mark" followed by its withdrawal to the "0.5 mark." Stability of the digital meter for 5 seconds was mandatory before recording the lengths. All measurements were repeated one week later and then both measurements were averaged to represent "APEX mark" and "0.5 mark," respectively. Data were analyzed using t-test, with significance set at 0.05. Results Regardless of the employment protocol, most registered lengths were longer than targeted. The mean "APEX mark" was significantly longer than the mean AL (P=0.000), and the mean "0.5 mark" was significantly longer than the mean RL (P=0.000). Although the mean "0.5 mark" was longer than the mean AL, the difference was not significant (P=0.07). Conclusion The apical level of the root canal targeted by the Root ZX was the apical foramen. The most accurate employment protocol to achieve that is to use the Root ZX according to the manufacturer's recommendations.

Influence of heat treatment of nickel-titanium instruments on the accuracy of an electronic apex locator integrated with endodontic motor

Context

Manufacturers have produced a wide variety of nickel-titanium (NiTi) alloys, but the available literature is limited on the accuracy of some integrated electronic apex locators (EAL) used with different NiTi heat treatments in working length (WL) determination.

Aim

This study aims to evaluate ex vivo , the influence of different heat treatments of NiTi instruments, and the diameter of the apical preparation on the accuracy of an EAL used during root canal preparation using an integrated EAL and motor unit.

Materials and Methods

Nineteen extracted human mandibular incisors were included in the study. The WL control was determined by the visual method. Instruments of Mtwo, Reciproc, Reciproc Blue, WaveOne Gold, Twisted File Adaptive, and Hyflex CM systems, with diameters from 0.25 mm to 0.50 mm, were used to measure WL during root canal preparation. The electrical resistivity of instruments with a diameter of 0.25 mm from each system was evaluated using an Inductance, Capacitance, and Resistance (LCR) meter.

Statistical Analysis Used

Data were statistically analyzed using Fisher's exact test and Kruskal-Wallis test.

Results

The different heat treatments and different diameters did not influence the precision of the EAL (P > 0.05).

Conclusion

The heat treatment and the diameter of the apical preparation did not influence the accuracy of WL determination by an EAL integrated with the endodontic motor.

Accuracy of working length measurement by Raypex 6: Electronic apex locator versus actual measurements under stereomicroscope

Background/Aim: This study aimed to evaluate the precision of the Raypex 6 apex locator in locating the apical constriction (AC) and major foramen (MF) during a root canal treatment compared with a microscopic evaluation. Another aim of the present study was to evaluate the accuracy of the Raypex 6 in the presence of different irrigating solutions (NaOCl, saline, EDTA, etidronic acid-HEBP). Material and Methods: One hundred and nine patients were included in this study and were randomly assigned into four groups according to the irrigation solution used; NaOCl, EDTA, HEBF and saline. Electronic MF (EMF) and AC (EAC) were measured by using Raypex 6. The teeth were extracted. The apical 3 mm of each canal was trimmed to expose the file tip. The samples were observed under a stereomicroscope, and the actual length of MF (ALMF) and AC (ALAC) were measured. The data were analyzed by using x2 test, and significance was set at P< 0.05. Results: The Raypex 6 was accurate 71.4% of the time to ±0.5mm and 93.3% of the time to ±1mm in determining the ALAC. While similar ALAC-EAC differences were observed in EDTA, NaOCl, and saline groups (p= 0.230), the highest differences were seen in the HEBP group (p= 1.000). The precision of Raypex 6 in determining the working length measurement depends on the type of irrigation. All solutions allowed reliable detection of AC. However, HEBF significantly increased the risk of overpreparation. Conclusions: Raypex 6 can be recommended for clinical use and its accuracy is not affected by the type of irrigant when locating MF.

Accuracy of Four Apex Locators in Premolars with Root Resorption: An In vitro Study

Introduction

The aim of the present in vitro study was to compare the accuracy of the working length measurements of four foramen locators: Root ZX mini, Raypex 6, Woodpex III and Propex Pixi in uniradicular premolars with simulated root resorption.

Materials and Methods

For this study, 30 single-rooted permanent premolars were selected. The samples were divided into two groups: 15 teeth with simulated external root resorption and 15 teeth with internal resorption. Each sample was immersed in containers with alginate covering only the root part. Measurements were acquired from the four foramen locators and compared with the working length measurements that have been previously obtained with the direct visual technique and the use of a Digital USB Microscope under 5×. Next, the Shapiro-Wilk normality test was applied. The ANOVA test and t-test for related samples were performed, in order to analyze the measurements obtained.

Results

In the teeth with external resorption, no statistically significant differences in the measurements were obtained with Raypex 6 and Propex Pixi foramen locators, but there were statistically significant differences with Root ZX mini and Woodpex III Root Zx mini [Root Zx mini (P=0.040) and Woodpex III (P=0.000)]. On the other hand, in the samples with internal root resorption, there were no statistically significant differences in measurements with the Root ZX mini, Propex Pixi and Raypex 6 foramen locators. However, there were significant differences with Woodpex III.

Conclusions

Based on this in vitro study, Raypex 6 had the highest accuracy in premolars with simulated external resorption and Root ZX mini was the most accurate in teeth with simulated internal resorption. Furthermore, external root resorption affects the accuracy of foramen locators more than internal resorption.

Influence of calcium hydroxide residues after using different irrigants on the accuracy of two electronic apex locators: An in vitro study

BACKGROUND

The purpose of this study was to evaluate the effect of calcium hydroxide (Ca[OH] ₂) residues on the accuracy of two electronic apex locators (EALs) (Root ZX and Raypex 6) in the presence of different irrigants.

MATERIALS AND METHODS

In this an in vitro study Eighty single-rooted human mandibular premolars were selected. The crowns of the teeth were removed to standardize the working lengths (WLs). Actual WLs (AWLs) were recorded, and the root canals were shaped using protaper rotary instruments up to size F3. Then, the root canals were dried and filled with injectable Ca (OH) ₂ paste and the access cavities were temporarily sealed. Teeth were put into four alginate boxes, including two experimental groups (n = 30) and two control groups (n = 10). The pools of alginate were wrapped in wet gazes and stored at 37°C and 100% humidity for 7 days. Then, the root canals were exposed and Ca (OH) ₂ paste was removed by normal saline or 5.25% sodium hypochlorite irrigation followed by 17% ethylenediaminetetraacetic acid (EDTA), and the electronic WL (EWL) was measured by Root ZX and Raypex 6. Differences of EWL from AWL were calculated. Furthermore, the percentage of acceptable measurements (tolerance limit of ± 0.5 and ± 1 mm) was calculated for each apex locator. One-way ANOVA test with post hoc paired t-test and Chi-square test was used to analyze the data (P < 0.05).

RESULTS

The results showed that there was no significant difference between the accuracy of two EALs and irrigants (P > 0.05).

CONCLUSION

The present study revealed that no statistically significant differences were observed between the two apex locators after Ca(OH)₂ paste removal with different irrigants.

A comparative assessment of the accuracies of Raypex 5, Raypex 6, iPex and iPex II electronic apex locators: An in vitro study

PURPOSE

The aims of this study were to examine the accuracy of iPex II and to compare it with those of Raypex 5, Raypex 6 and iPex electronic apex locators (EALs).

MATERIALS AND METHODS

Thirty fresh human mandibular premolar teeth were used in this study. Crown segments were cut and root canals were coronally flared. A #10 K-file was inserted until its tip can be seen within apical foramen to determine actual working length (AWL). Teeth were embedded in alginate and each multi-frequency EALs were randomly tested to determine the electronic working length (EWL). Differences between AWLs and EWLs were statistically compared.

RESULTS

No significant differences were found between four EALs. EWL measurements by Raypex 5 were accurate in 64.29%, Raypex 6 in 53.58%, iPex in 64.29% and iPex II in 50% of the specimens, within the range of ±0.5 mm from the AWL.

CONCLUSION

Within the limitations of this in vitro experiment, our findings indicate that the accuracy of working length measurements calculated with iPex II was similar to those of other multi-frequency EALs used in this study.

A comparative clinical evaluation of accuracy of six apex locators with intraoral periapical radiograph in multirooted teeth: An in vivo study

AIM

The purpose of this clinical study was to compare and clinically, to evaluate the accuracy of six apex locators with intra oral periapical (IOPA) radiograph in multirooted teeth.

MATERIALS AND METHODS

A total of 90 multirooted teeth (maxillary and mandibular molars) with irreversible, infected or necrotic pulp tissue and completely formed roots were included in this study and were divided randomly into six groups (Root ZX II, Raypex 6, I-Root, Romiapex A-15, Sybron Endo Mini and Root ZX mini). The working length was determined using six different apex locators, and the accuracy of the apex locators was compared with IOPA radiographs, to be categorized as accurate, short, and long or beyond.

RESULTS

A total of 270 canals were evaluated, of which 233 (86.3%) canals exhibited acceptable working length, 28 (10.4%) canals exhibited short working length, and only 9 (3.3%) canals exhibited working length beyond the apex. There were a statistically significant results in all the groups (P < 0.05) and the comparison between the groups was statistically insignificant.

CONCLUSION

The repeatability with that of apex locators is of great advantage, but the information gained from the radiographs cannot be obtained by any other means. Therefore, it is recommended that radiograph and apex locators are the best combinations in accurately determining the working length and the successful endodontics.

The Effect of File Size and Type and Irrigation Solutions on the Accuracy of Electronic Apex Locators: An In Vitro Study on Canine Teeth

Measurements of the root canal during endodontic treatment have a significant influence on the course of the therapeutic process as well as on its final result in both human and veterinary medicine. The apical constriction should be the termination point for the preparation and filling of the root canal. This research was conducted with the use of a Septodont kit consisting of a small chamber filled with the examined solution in which a healthy second incisor was placed. The step back method was applied for the root canal preparation and master apical file of 30 was used. The working length was 22 mm. The examination was conducted with the use of steel as well as nickel titanium hand instruments. Different irrigation solutions and two types of apex locators were used. Measurements of the working length of the root canal showed dependence on the size of the instrument. Examinations carried out in various environments showed that analogical measurements were obtained only for sodium hypochlorite solutions. In other environments the measured sections were shortened. Comparative examinations with the use of steel instruments demonstrated insignificant measurement differences. Compared to these results, the measurements in nickel titanium group were characterized by more considerable deviations.

Comparative evaluation of the accuracy of two electronic apex locators in determining the working length in teeth with simulated apical root resorption: An in vitro study

Introduction:

Accurate determination of working length (WL) is a critical factor for endodontic success. This is commonly achieved using an apex locator which is influenced by the presence or absence of the apical constriction. Hence, this study was done to compare the accuracy of two generations of apex locators in teeth with simulated apical root resorption.

Materials and Methods:

Forty maxillary central incisors were selected and after access preparation, were embedded in an alginate mold. On achieving partial set, teeth were removed, and a 45° oblique cut was made at the apex. The teeth were replanted and stabilized in the mold, and WL was determined using two generations of apex locators (Raypex 5 and Apex NRG XFR). Actual length of teeth (control) was determined by visual method.

Statistical Analysis:

Results were subjected to statistical analysis using the paired t-test.

Results:

Raypex 5 and Apex NRG was accurate for only 33.75% and 23.75% of samples, respectively. However, with ±0.5 mm acceptance limit, they showed an average accuracy of 56.2% and 57.5%, respectively. There was no significant difference in the accuracy between the two apex locators.

Conclusion:

Neither of the two apex locators were 100% accurate in determining the WL.