The ability of Reciproc instruments to reach full working length without glide path preparation: a clinical retrospective study

Impact of Different Glidepath Techniques on the Overall Performance of WaveOne Gold in an Artificial S-Shape Canal

OBJECTIVES

The article's aim is to test if rotary or reciprocating glide path influences the overall performance of WaveOne Gold in S-shaped canals.

METHODS

Sixty endo training blocks with an S-shape curvature were divided into three groups based on the glide path method used: no glide path; glide path preparation with ProGlider; glide path preparation with WaveOne Gold Glider. All blocks were then shaped with WaveOne Gold Primary. The time for shaping, the incidence in reaching working length and the number of pecking motions were recorded. ANOVA with Turkey's test was used, and the p-value was set to 0.05.

RESULTS

WaveOne Gold Primary reached working length faster in the control group when comparing total working times. No significant differences in the ability of the WaveOne Gold Primary to reach working length in all groups (p > 0.05). The mean number of pecking motions was higher in the control group compared to other groups.

CONCLUSIONS

No significant differences in the time needed to achieve a glide path between Proglider and WaveOne Gold Glider. WaveOne Gold Primary can shape a double curved canal faster if a glide path is present but takes less time to reach length if it is the only file used. No difference in the ability to reach working length.

Comparative evaluation of cleaning efficiency of single file NiTi rotary system during root canal treatment procedure - A scanning electron microscope study

Background

Optimal biomechanical preparation, thorough irrigation, proper disinfection, and finally, well-sealed obturation is a must to attain definitive success in root canal procedure. Proper preparation of the root canal is all the more imperative to establish a hermetic apical seal with adequately placed filling materials. The present study was conducted for comparing the Cleaning Efficiency of F360 system and the WaveOne Gold (WOG) system of rotary NiTi instrumentation for a root canal.

Materials and Methods

One hundred freshly extracted noncarious mandibular canines were obtained. Access cavity of standard size was made followed by the establishment of working length. Afterward, random division of all the specimens was done into two study groups: group A: the group in which F360 system was used for instrumentation and group B: the group in which the WOG system was used for instrumentation. Irrigations of all the specimens of both the study groups were done followed by root canal shaping by the instrument system of their respective study groups. Scanning electron microscope (SEM) was used for assessment after specimens were cut buccolingually. Debris score and residual smear layer score were used for assessment.

Results

Among group A specimens, the mean smear layer score at the coronal third, middle third, and apical third was 1.76, 2.39, and 2.65, respectively. Among group B specimens, the mean smear layer score at the coronal third, middle third, and apical third was 1.34, 1.59, and 1.92, respectively. While analyzing statistically, it was seen that the mean smear layer score was significantly higher among specimens of group A in comparison to group B. While analyzing statistically, it was seen that the mean debris score was significantly higher among specimens of group A in comparison to group B.

Conclusion

The cleaning effectiveness of WOG instruments was significantly enhanced in comparison to F360 equipment.

Comparison of Cleaning Efficiency of Root Canal Using Different Rotary NiTi Instrumentation System: A Scanning Electron Microscopic Study

Background: To ensure that endodontic treatment is as effective as possible, it is important to remove any smear layer that forms as part of the instrumentation procedure. This layer might reduce the overall effectiveness of endodontic therapy.

Aim of the study: For this research, two distinct types of rotary NiTi files were compared: WaveOne Gold (WOG) (Dentsply Maillefer, Ballaigues, Switzerland) and F360 (Komet Brasseler GmbH & Co., Lemgo, Germany) for its capacity to eliminate trash and the smear layer.

Materials and methods: Two groups (n=20 each) of 40 mandibular second premolar teeth were employed in this investigation, with each group receiving a random allocation of teeth. The F360 system and the WaveOne Gold system are two sets of instruments. The samples were irrigated with a mixture of sodium hypochlorite (NaOCl) (5.25%) and citric acid (40%). Finally, all samples in the centre of the coronal, middle, and apical thirds were examined by scanning electron microscopy (SEM). Mann-Whitney U tests were used to analyse the data.

Results: F360 instrument showed a statistically significant difference for smear layer removal among all thirds of the root canal whereas WOG resulted in a significant difference when the apical third was compared to the middle and coronal third. Significant differences were found in the middle and apical third in terms of smear layer removal between the two groups.

Both F360 and WOG instruments showed statistically significant differences for debris removal among all thirds of the root canal. No significant differences were found in the coronal, middle, and apical third in terms of debris removal between the two groups.

Conclusion: WOG resulted in cleaner canals compared to the F360 file system at coronal, middle, and apical third.

Influence of glide path kinematics during endodontic treatment on the occurrence and intensity of intraoperative and postoperative pain: a systematic review of randomized clinical trials

BACKGROUND

Preliminary canal enlargement (glide path preparation) may play a significant role in the development of pain. The aim of this systematic review of randomized clinical trials was to assess the influence of glide path kinematics during endodontic treatment on the occurrence and intensity of intraoperative and postoperative pain.

METHODS

A search was performed in June 2019 in six electronic databases (PubMed, Scopus, LILACS, SciELO, Embase and Web of Science) and two grey literature databases (OpenGrey and OpenThesis). The bibliographic references of the eligible articles were also hand-searched. The included clinical studies assessed the occurrence and intensity of intraoperative and/or postoperative pain after root canal preparation without glide path preparation (WGP) or with glide path preparation using manual (M-GP), continuous rotary (CR-GP), or reciprocating (R-GP) instruments. The primary outcome was the occurrence and intensity of intraoperative and postoperative pain, while analgesic consumption was the secondary outcome. The full texts of the eligible studies were analyzed by two reviewers who performed calibration exercises to verify the risk of bias and quality of the individual studies using the Joanna Briggs Institute Critical Appraisal tool.

RESULTS

From 1283 identified articles, only six studies were included in the qualitative analysis of the results, with a total sample of 884 patients/teeth. Three studies presented a high risk of bias, while three studies presented a moderate risk. Two studies reported that CR-GP causes lower pain levels than M-GP and WGP, and three studies showed no differences between CR-GP and R-GP. Regarding analgesic consumption, two studies found no differences among glide path kinematics, and one study reported lower consumption for CR-GP than for M-GP. Because of the limited number of studies and methodological differences, no statistical analyses were performed for the glide path kinematics comparisons.

CONCLUSIONS

Compelling evidence indicating a significantly different occurrence and intensity of pain among glide path kinematics is lacking. The systematic review protocol was registered in the PROSPERO database [CRD42020139989].

Undergraduate Students' Acceptance of a Reciprocating One-File System for Endodontic Treatment

OBJECTIVES

Reciprocating endodontic one-file systems are a comparatively new method for root canal shaping. Even though the mechanical properties are comparable to modern rotating mechanical systems, data about subjective assessment and application quality are scarce. This study evaluates the reciprocating one-file system in undergraduate education.

MATERIALS AND METHODS

A total of 42 undergraduate students without experience regarding reciprocating file systems filled in a questionnaire in four different points in time (t ₁-t ₄) anonymously. The questionnaire was based on a numerical rating scale ranging from 0 to 10.

STATISTICAL ANALYSIS

A least significant difference post-hoc analysis comparing the group average values was performed. The adjusted level of significance was p < 0.004 after Bonferroni correction.

RESULTS

All rating scores increased after the first theoretical instruction. After the first practical training in artificial root canals in resin blocks and extracted teeth (t ₂), the estimation of "time efficiency" (p = 0.002), "handling" (p < 0.001), and "overall impression" (p < 0.001) improved significantly. The "overall impression" remained constant and showed no significant changes after the first practical training.

CONCLUSIONS

Reciprocating systems seem to show a good acceptance among first time users. Initial concerns about "work safety" decrease during every step of the educational process. Reciprocating one-file systems are a safe and well-accepted method in undergraduate teaching.

Influence of Negotiation, Glide Path, and Preflaring Procedures on Root Canal Shaping-Terminology, Basic Concepts, and a Systematic Review

INTRODUCTION

Negotiation, glide path, and preflaring are essential steps in root canal shaping procedures. This report aimed to discuss the terminology, basic concepts, and clinical considerations of negotiation, glide path, and preflaring procedures and the influence of these steps on root canal shaping.

METHODS

This systematic review was undertaken following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The protocol has been registered with the International Prospective Register of Systematic Reviews (number CRD42019127021). A comprehensive literature search was performed by 2 independent reviewers using a selected search strategy in 2 electronic databases (PubMed and Scopus) until January 28, 2019. A further search was performed manually in endodontic journals. Studies investigating or comparing at least 1 shaping property resulting from root canal instrumentation with a glide path or preflaring in human extracted teeth or clinical studies were included.

RESULTS

The literature shows that the definition of glide path and preflaring procedures remains controversial, which requires an elaboration in the American Association of Endodontists' Glossary of Endodontic Terms. After the removal of irrelevant and duplicated articles, 98 articles were included. The impact of glide path preparation and preflaring on working length determination, apical file size determination, canal transportation, separation of endodontic files, shaping time, dentinal microcrack formation, and extrusion of debris was discussed. Because of heterogeneity among the included studies, quantitative synthesis was not performed for most of the parameters.

CONCLUSIONS

An evidence-based guideline is needed to define and correlate the basic concepts and current applications of each step of contemporary advancements in root canal instruments. Glide path preparation reduces the risk of debris extrusion, has no influence on the incidence of dentinal crack formation, and improves the preservation of the original canal anatomy. The creation of a glide path may have no impact on Reciproc files (VDW, Munich, Germany) in reaching the full working length. Preflaring increases the accuracy of working length determination. Further randomized clinical trials are required to evaluate the effect of a glide path and preflaring on root canal treatment outcomes.

A retrospective assessment of different endodontic treatment protocols

Background

The aim of this study was to assess the clinical impact of non-surgical root canal treatments (NSRCT) performed with different treatment protocols on the probability of tooth survival without untoward events and to identify predictors influencing the outcome.

Methods

During the period from July 1999 to October 2016, 5,858 patients were identified in which 9,967 NSRCTs were performed. The treatments were followed up and divided into three groups. In Group 1 root canal treatment was performed with hand instruments, in Group 2 with multiple file rotary instruments and passive ultrasonic irrigation (PUI), and Group 3 was treated with Reciproc instruments and PUI. Untoward events were defined as orthograde retreatment, apicoectomy or extraction of the tooth after initial treatment. Weibull regression was used to analyse the data.

Results

A total of 9,938 cases could be included into the analyses. The results showed 5-years predicted survival rates without untoward events of 73.9% (95% CI [71.7%–76.1%]), 75.1% (95% CI [71.7%–78.0%]) and 78.4% (95% CI [75.1%–81.4%]) for study group 1 (N = 5,580), 2 (N = 1,700) and 3 (N = 2,658), respectively. The differences between Group 1 and 3 were statistically significant (p < 0.006). Higher age of the patient (per year increase) and number of earlier NSRCTs (per unit increase) reduce the survival without untoward events statistically significant (both p < 0.02), while treatment of premolars had a statistically significant lower hazard ratio [0.89 (95% CI [0.79–0.99]; p = 0.030)] compared to treatment of molars and anterior teeth. A higher number of supportive periodontal treatments (per unit increase) improved tooth survival without untoward events highly significant (p < 0.0001).

Discussion

More recent endodontic treatment protocols involving reciprocating instruments and PUI appear to be associated with higher tooth survival rates without untoward events compared to hand instruments.

Shaping effectiveness and surface topography of reciprocating files after multiple simulated uses

This in vitro study assessed morphological changes and efficiency of reciprocating files after multiple uses. Sixty standardized Endo Training Blocks and 10 ReciprocR25 files were selected (six blocks for each file). Each file was its own control (before use vs. after each instrumentation). The instruments were used according to the manufacturer's instructions, and scanning electron microscopy was used to observe fatigue cracks, metal strips/metal flash, pitting, fretting, debris, disruption of the cutting edge, and plastic deformations after each instrumentation. The presence of seven wear variables was scored semiquantitatively by viewing micrographs collected before and after use. The prepared areas in resin blocks were calculated and compared by using AutoCAD software. The control group had significantly lower values for all wear variables except fretting and plastic deformation. The presence of fatigue cracks and metal strips/metal flash significantly differed between unused instruments and instruments used four or five times, in all observed sections. The area of instrumented Endo Training Blocks significantly differed in relation to the number of instrument uses. The Reciproc files wore progressively, and repeated use affected their shaping efficiency in simulated canals.

Performance of Reciproc Blue R25 Instruments in Shaping the Canal Space without Glide Path

INTRODUCTION

This study assessed the frequency in which Reciproc Blue R25 instruments (VDW, Munich, Germany) reached the full working length (WL) of mandibular molar canals without a glide path. The influence of the type of electric motor (ie, conventional corded or cordless) on the instrument's performance was also assessed.

METHODS

One hundred mandibular molars with slight to moderate root canals were selected and randomly assigned into 1 of 2 experimental groups according to the type of electric motor used: conventional corded (VDW Silver, VDW) or cordless motors (VDW.CONNECT Drive, VDW). Therefore, 50 molars and 154 root canals were selected for each motor. Reciproc Blue R25 instruments were used until reaching two thirds of the estimated WL. Then, a size 10 K-file was passively inserted to determine the full WL. No active instrumentation movement was performed with a size 10 K-file. Independently, whether a size 10 K-file reached the apex or not, Reciproc Blue R25 instruments were used to complete canal preparation. When the Reciproc Blue R25 instrument was able to reach the full WL, the case was classified as "reaching the full working length" (RFWL). If the instrument was not able to reach the full WL, the case was classified as "not reaching the full working length" (NRFWL). The chi-square test of goodness of fit was used to verify whether the observed frequencies of RFWL and NRFWL adhered to the expected ones. A 5% cutoff level of significance was considered for statistical assumptions.

RESULTS

Reciproc Blue R25 instruments were able to reach the full WL in 304 root canals (98.70%). The chi-square test revealed the observed frequencies of RFWL and NRFWL to be significantly different from the expected frequencies (χ² = 292,208, P = .000). The frequency of RFWL and NRFWL was exactly the same for both types of electric motors. No instrument fractured, and a single file deformed. In 50 of 308 root canals, a size 10 K-file was unable to passively reach the full WL. From these 50 canals, Reciproc Blue R25 instruments were able to reach the full WL in 47 of them.

CONCLUSIONS

Reciproc Blue R25 instruments were able to reach the full WL in a high frequency of cases. The type of electric motor used did not interfere in the frequency of RFWL cases. No instrument fractured, and a single file deformed.

Shaping ability of the profile 25/0.06 and protaper F2 in rotary motion, and reciproc in simulated canals

Background

Since the introduction of nickel–titanium (Ni–Ti) instruments to dentistry, a wide variety of Ni–Ti instruments have become commercially available. These Ni–Ti instruments are expensive, which limits their usage in developing countries and forces practitioners to use instruments repeatedly. Another problem is the possible prion cross-contamination associated with the multiple usage of endodontic instruments. In addition, the use of these instruments requires new skills and experience. In this article, the shaping capacities of two conventional rotary file systems, ProFile 25/0.06 and ProTaper F2, were reviewed and compared with the Reciproc single-file system.

Methods

A total of 45 simulated canals with 40° curvature, in clear resin blocks, were prepared using conventional rotary systems consisting of ProFile orifice shaping (OS) #3 and final flaring #25/.06, Reciproc R25, and ProTaper shaping file SX and finishing file F2. Pre-and post-instrumentation images were analyzed at ten different levels, using AutoCAD 2007 software. The measurement positions were defined in 1-mm intervals: positions 0–3 established the apical part, positions 4–6 constituted the middle part, and positions 7–10 established the coronal part of the canal. The amount of removed resin, the transportation, instrumentation time, change in working length (WL), instrumentation fractures, and the presence of ledge were evaluated. Data were analyzed using ANOVA, Kruskal–Wallis and independent t-test (p < 0.001).

Results

ProFile removed the least resin (p < 0.001) and caused less transportation than Reciproc and ProTaper, in total (p < 0.001). ProTaper caused more transportation ProFile and Reciproc in the apical part (p < 0.000). Reciproc caused more transportation than ProTaper and ProFile (p < 0.001), and the transportation tendency toward the inner aspect of the curvature in the middle part. Reciproc caused the less transportation than ProFile and ProTaper in the coronal part. The transportations tended to occur toward the outside of the curvature, except the middle part with Reciproc and at points 5 and 6 with ProTaper. There were no significant differences among the groups in terms of maintaining the original WL. Reciproc was significantly faster than the others group (p < 0.001). Only one instrument fracture (25/0.06 ProFile) was noted. All groups showed one ledge each.

Discussion

The results of the present study showed that both ProFile 25/06 and ProTaper F2, combined with a file used for coronal enlargement (OS3 and SX), have the potential to create satisfactory canal shape in the curved root canals. Further studies using real human teeth are needed to confirm our results.

Comparison of the ability of Reciproc and Reciproc Blue instruments to reach the full working length with or without glide path preparation

OBJECTIVES

The purpose of the present study was to compare the mean preparation times and frequency with which Reciproc and Reciproc Blue instruments reached the full working length in mandibular molars, with or without glide path preparation.

MATERIALS AND METHODS

Previously untreated mesiobuccal and mesiolingual canals with completely formed apices were randomly divided into 6 groups (n = 50) depending on the usage of Reciproc (RC; VDW), Reciproc Blue (RC Blue; VDW), C-Pilot (CP; VDW), and R-Pilot (RP; VDW) files: RC, RC Blue, RC + C-Pilot (RC-CP), RC-Blue + C-Pilot (RC Blue-CP), RC+R-Pilot (RC-RP), and RC Blue + R-Pilot (RC Blue-RP). A glide path was prepared using the hand-operated C-Pilot or the machine-operated R-Pilot instruments, respectively. The χ2 test, analysis of variance, and the Tukey post hoc test were used for statistical comparisons.

RESULTS

No statistically significant differences were observed in the distribution of the frequency of reaching the full working length in the RC (94%), RC Blue (88%), RC-CP (94%), RC Blue-CP (90%), RC-RP (96%), and RC Blue-RP (92%) groups (p > 0.05).

CONCLUSIONS

Preparation of a glide path did not have a significant effect on reaching the full working length using these systems.