Reciprocating kinematics leads to lower incidences of postoperative pain than rotary kinematics after endodontic treatment: A systematic review and meta-analysis of randomized controlled trial

Fifteen years of engine-driven nickel-titanium reciprocating instruments, what do we know so far? An umbrella review

Numerous systematic reviews (SRs) have produced conflicting findings on engine-driven nickel-titanium reciprocating instruments (reciprocating instruments) since Yared's seminal study 15 years ago. This umbrella review analysed SRs examining the clinical and laboratory evidence regarding reciprocating instruments for root canal treatment. SRs that evaluated qualitatively and/or quantitatively the outcomes postoperative pain, oral health-related quality of life (OHRQoL), shaping ability, debris extrusion, microbial load, endotoxins reduction, cyclic fatigue, file fracture, dentinal cracks and root canal filling removal were included. The AMSTAR 2 tool was used to evaluate SRs quality, while the ROBIS tool to assess risk of bias (RoB). Forty SRs were included. The SRs revealed predominantly 'high' RoB and 'critically low' quality. Most focused on technical outcomes, exhibiting significant methodological and statistical heterogeneity. Findings suggest comparable efficacy between reciprocating and rotary instruments. However, due to the scarcity of high-quality evidence, future well-designed studies and reviews considering core outcome measures are needed.

Endodontic Ni-Ti Rotary Instruments for Glide-path, Are They Still Necessary and How to Think about the Ideal Instrument?

How to cite this article: Reda R, Maccari E, Bhandi S. Endodontic Ni-Ti Rotary Instruments for Glide-path, Are They Still Necessary and How to Think about the Ideal Instrument? J Contemp Dent Pract 2024;25(6):505-506. Keywords: Alloy, Endodontics, Glide Path, NiTi Rotary Instruments, Patency.

Postoperative pain after single-visit root canal treatments in necrotic teeth comparing instruments' kinematics and apical instrumentation limits - a prospective randomized multicenter clinical trial

OBJECTIVES

This prospective randomized multicenter clinical trial (PRMCT) investigated postoperative pain after single-visit root canal treatments in teeth affected by pulp necrosis (PN), and asymptomatic apical periodontitis (AAP) (with apical radiolucent areas) or normal periradicular tissues (without apical radiolucent areas) comparing different instruments' kinematics and apical instrumentation limits.

METHODS

Before chemomechanical preparation, 240 patients/teeth were randomly distributed into four groups (n = 60) according to the instruments' kinematics (rotary or reciprocating) and apical instrumentation limits (with or without intentional foraminal enlargement [IFE]). After that, specimens were submitted to the same irrigation and obturation techniques, and the patients were referred to undergo the definitive restorations. No medication was prescribed, but the patients were instructed to take either paracetamol (750 mg every 6 h for three days) or ibuprofen (600 mg every 6 h for three days) in pain cases. Postoperative pain incidence and levels were assessed at 24-, 48-, and 72 h following treatment completion according to a verbal rating scale (VRS) following a score. The Kolmogorov-Smirnov test was applied to assess the normality of the data. Mann-Whitney U, Chi-square, Friedman's ANOVA, and Friedman's multiple 2 to 2 comparison tests were employed to identify potential significant statistical differences among the variables in the study groups (P < .05).

RESULTS

Significant statistical differences were only observed among the groups considering tooth, periradicular status, and the occurrence of overfilling (sealer extrusion) (P < 0.00). Patients with teeth instrumented through rotary kinematics and without IFE experienced lower rates of postoperative pain; however, this difference was relevant only at 24 h (P < 0.05).

CONCLUSIONS

Postoperative pain was lower after using a rotary file system (Profile 04) inserted up to the apical constriction (AC). However, this finding was just statistically meaningful at 24 h.

TRIAL REGISTRATION

This PRMCT was approved by the Human Research Ethics Committee of the Paranaense University - UNIPAR, Francisco Beltrão, PR, Brazil (CAAE. 46,774,621.6.0000.0109) on 02/09/2021. It was registered at The Brazilian Registry of Clinical Trials - ReBEC (RBR-3r967t) on 01/06/2023, was performed according to the Principles of the Helsinki Declaration and is reported following the Consolidated Standards of Reporting Trials Statement.

Can instrumentation kinematics affect postoperative pain and substance P levels? A randomized controlled trial

BACKGROUND

This study aimed to assess the influence of continuous rotation and reciprocation kinematics on postoperative pain (POP) levels and substance P (SP) levels in patients diagnosed with irreversible pulpitis and symptomatic apical periodontitis (SAP).

MATERIALS AND SUBJECTS

A total of twenty patients were randomly assigned into two groups: Continuous Rotation Group (CRG) (n = 10), subjected to mechanical preparation with the EdgeEndox7 rotary system (Albuquerque, NM, USA), and Reciprocation Group (RG) (n = 10), treated with the EdgeOne Fire reciprocating system (Albuquerque, NM, USA). Apical fluid (AF) samples were collected, and SP levels were quantified through radioimmunoassay. POP was assessed using the Numerical Rating Scale (NRS) at various time intervals (preoperatively, 6 h, 12 h, 24 h, 48 h, and 72 h). Data were statistically analyzed utilizing the independent t-test, Mann-Whitney U test, Friedman's test, and Nemenyi post hoc test.

RESULTS

There was a significant increase in SP levels in the reciprocating group compared to the continuous rotation group (P ≤ 0.05). Additionally, patients in the reciprocating group reported significantly higher POP levels (P ≤ 0.05) at all measured intervals (6 h, 12 h, 24 h, and 48 h), with both groups exhibiting similar pain level reductions at the 72-hour mark.

CONCLUSION

Our findings suggest that continuous rotation kinematics in root canal preparation leads to a considerable reduction in SP expression and POP.

TRIAL REGISTRATION

The study protocol was retrospectively registered on the www.

CLINICALTRIALS

gov database (NCT06081335) at (13/10/2023) after the approval of the Ethics Committee, Faculty of Dentistry, Ain Shams University (FDASU-RecIM012135).

Post-Operative Quality of Life after Single-Visit Root Canal Treatment Employing Three Different Instrumentation Techniques-An Institutional Randomized Clinical Trial

Root canal treatment (RCT) eliminates damaged pulpal tissue and protects the tooth from recurrent microbial invasion. Post-endodontic pain (PEP) is a frequently encountered complication of root canal therapy. It can have an impact on patients' quality of life (QoL) and their subjective perception of treatment options. Thus, a self-assessment questionnaire was used to evaluate and compare the influence of manual, rotary, and reciprocating file shaping procedures on immediate post-operative quality of life (POQoL) involving single-visit root canal therapy. It was a double-blinded, randomized, controlled clinical trial. A total of 120 participants were randomly assigned sequentially to three groups comprising 40 patients in each group: Group A: Hand K file (positive control); Group B: ProTaper Next file system; and Group C: WaveOne Gold. Post-operative pain was evaluated using a 4-point visual analog scale (VAS) after 12 h, 24 h, 48 h, 72 h, and 1 week. The highest post-operative pain was with manual instrumentation using hand K files, and the lowest was with reciprocating and rotating instrumentations. No significant difference was noted between the parameters of quality of life assessed, suggesting the filing system or technique had a similar effect.

The Effect of Number of Visits, Use of Solvent and Gutta-percha Removal Technique on Postoperative Pain following Nonsurgical Endodontic Retreatment; A Systematic Review and Meta-analysis

Introduction

The nonsurgical endodontic retreatment (NERT) is the first choice of dental ministration when primary/initial endodontic treatment fails. The present study aimed to investigate the presence of postoperative pain (POP) after NERT in permanent asymptomatic teeth as well as possible factors associated with POP.

Materials and Methods

A comprehensive search of literature was performed in Pubmed/MEDLINE, Embase, Scopus and Web of Science databases, up to January 2023; including randomized clinical trials and prospective studies. The risk of bias was assessed with RoB 2.0 and ROBINS-I tools. Subgroups analyses were conducted to evaluate the differences in the incidence or level of POP between the number of visits, the use/not use of solvent, the removal technique of gutta-percha, and the period of POP analysis. Mean differences and confidence intervals (CI) of 95% were used as measures of effect, and meta-regression was used along with subgroup analysis. The certainty of evidence was assessed using GRADE, and the probability value of <0.05 was considered significant.

Results

Twenty-four studies were selected, with thirteen included in the meta-analysis. There was a statistical difference between the incidence of POP after 24 h (95% CI, 0.28 to 0.52) and one week (95% CI, 0.02 to 0.13) from the endodontic retreatment (P<0.01). However, there was no statistical difference between different techniques, number of visits and use of solvent (P>0.05) in the same period. In addition, the certainty of evidence was very low.

Conclusions

Post-operative pain is a common response to NERT, independent of the retreatment technique(s) applied, number of visits and use of solvent(s); with very low certainty of evidence as well as low risk of bias. Moreover, the current analysis showed a (very) serious risk of inconsistency and imprecision. However, POP was significantly reduced within 1 week of the NERT.

Comparison of the incidence of postoperative pain in single sitting root canal treatment after using two reciprocating systems and two continuous rotary systems: An in vivo study

Aim

The aim of the present study was to compare the incidence of postoperative pain in single sitting root canal treatment after using two reciprocating and two continuous rotating file systems.

Methodology

One hundred and four permanent mandibular canine and first premolar teeth were selected for the study and were divided into two groups 1 and 2 comprising 52 teeth each. Group 1 was treated using reciprocating file systems and was subdivided into two subgroups A and B using WaveOne Gold (WOG) and Reciproc Blue (RB), respectively. Group 2 was treated using continuous rotating file systems and was divided into two subgroups A and B using One Curve (OC) and Vortex Blue (VB), respectively. Treatments were performed in a single sitting. After the visit, the patients were given a prescription for ibuprofen 400 mg to be taken every 6 h if they experience pain. Participants were asked to rate the intensity of the postoperative pain on a visual analog scale according to four classes (no pain, mild pain, moderate pain, and severe pain) after 24 h, 48 h, 72 h, and 7 days. Patients were also asked to record the number of prescribed analgesic medication tablets taken at these time points.

Results

There was a statistically significant difference (P = 0.00) among the reciprocating file systems and continuous file systems regarding the incidence of postoperative pain after 24, 48, and 72 h which signifies that pain incidence and duration is less with respect to reciprocation instrumentation as compared to continuous instrumentation.

Conclusion

The use of Reciproc instrumentation system (WOG and RB) showed significantly less intensity and duration of posttreatment pain compared to the single-file rotary system (OC and VB) in patients with symptomatic irreversible pulpitis with apical periodontitis.

Severity of Post-Operative Pain after Instrumentation of Root Canals by XP-Endo and SAF Full Sequences Compared to Manual Instrumentation: A Randomized Clinical Trial

This investigation aimed to examine the post-operative pain experienced following single-visit root canal treatment using the XP-endo shaper sequence (XPS), full-sequence self-adjusting file (SAF), and manual K-files (HKF). A randomized equivalence parallel design, double-blinded clinical study was conducted on 120 patients with symptomatic irreversible pulpitis, with or without clinical signs of apical periodontitis. Only teeth with fully formed roots and no periapical lesions were incorporated in the study. Patients were apportioned to one of three groups (n = 40) randomly: Group 1-XPS, Group 2-SAF, and Group 3-HKF. Pre- and post-instrumentation pain was rated utilizing Visual Analog Scale (VAS) with a spectrum of 0-100 mm. The descriptive statistics and one-way ANOVA with 95% confidence intervals were used for statistical analysis. The mean VAS scores before instrumentation were consistent in all three groups. At 6, 24, 48, and 72 h, patients with root canals instrumented by SAF had the lowest post-instrumentation mean VAS score, followed by XPS. For all time intervals, the patients in the HKF group had the highest VAS score. The full-sequence SAF instrumentation resulted in less post-operative pain than the XP-endo plus protocol, while manual instrumentation with K-files resulted in the highest post-operative pain.

Post-Operative Endodontic Pain Management: An Overview of Systematic Reviews on Post-Operatively Administered Oral Medications and Integrated Evidence-Based Clinical Recommendations

Endodontic treatment comprises the overall management of pre-, intra- and post-operative symptoms, including post-operative endodontic pain, considered as a complication susceptible of chronicization. Post-operative pain is very common and highly unpreventable and has a multi-factorial etiology and a potential pathogenic link to the acute inflammation of the periapical area, secondary to localized chemical, mechanical, host and/or microbial damage occurring during endodontic treatment. Considering the multitude of heterogeneous technical and pharmacological approaches proposed to control post-operative endodontic pain, the present study primarily comprised an overview of systematic reviews of systematic reviews of randomized clinical trials, summarizing findings on post-operatively administered oral medications for post-operative endodontic pain control, in order to note the most effective type and dosage of such drugs. Secondarily, a narrative review of the current evidence on technical solutions to be observed during endodontic treatment procedures, to control post-operative pain, was conducted to provide integrated evidence-based clinical recommendations for optimal post-operative endodontic pain management.

Instrumentation Kinematics Does Not Affect Bacterial Reduction, Post-Operative Pain and flare-ups: A Randomized Clinical Trial

AIM

This randomized clinical trial aimed to assess the effect of instrumentation kinematics (reciprocation or continuous rotation) on bacterial reduction, post-operative pain and incidence of flare-ups after root canal treatment of single-rooted mandibular premolars with asymptomatic apical periodontitis.

METHODOLOGY

Sixty-six patients were included in this prospective, parallel, randomized clinical trial. Patients were randomly allocated into two groups (N=33) according to the kinematics of the shaping instrument: WaveOne Gold (WO) used in reciprocation or One Shape (OS) used in continuous rotation. Under complete asepsis, bacterial samples were taken before (S1) and after (S2) a standard cleaning and shaping protocol. Evaluation of bacterial reduction was done by both culture technique and quantitative real-time polymerase chain reaction (qPCR) analysis. Post-operative pain was evaluated using the visual analog scale (VAS) after 24, 48- and 72-hours following treatment, while flare-ups were recorded as a binary outcome (Yes/No). Independent and paired t-tests were used for inter and intragroup comparisons for bacterial count data respectively. For post-operative pain score, intergroup comparisons were analyzed using Mann-Whitney U test while intragroup comparisons were analyzed using Friedman test followed by pairwise comparisons utilizing Wilcoxon signed rank test with Bonferroni correction. The significance level was set at p≤0.05 within all tests.

RESULTS

All the allocated participants received the intervention and were analyzed. The comparison between culture and qPCR methods showed that qPCR analysis demonstrated significantly higher pre-instrumentation baseline bacterial count (p<0.05). The percentage of bacterial reduction, detected by either method, significantly decreased after instrumentation using either rotation or reciprocation kinematics (p<0.05). However, the difference between the WOG or OS files was statistically non-significant (p>0.05). The intra-group comparisons showed a significant reduction in post-operative pain with time (p<0.05) for both groups. However, the inter-group comparison demonstrated that the difference in post-operative pain after the use of either WOG or OS was statistically non-significant (p>0.05). The incidence of flare-ups between both groups was also not-significant (p=1).

CONCLUSIONS

Shaping kinematics, either rotation or reciprocation motions, had no impact on bacterial reduction and the incidence of post-operative pain and flare-ups after root canal preparation of single-rooted premolars with asymptomatic apical periodontitis.

Assessment of postoperative pain after single-visit root canal treatment using rotary and reciprocating file systems: an in vivo study

Background

Various instrument kinematics used in single-visit endodontics influence the occurrence of pain after endodontic therapy. This study aimed to evaluate the occurrence of pain after mechanical instrumentation with Hyflex EDM (HEDM) and WaveOne Gold (WOG) during single-visit endodontic therapy.

Methods

Sixty patients diagnosed with asymptomatic irreversible pulpitis and normal apical tissues in mandibular premolar teeth were included in the study for single-visit root canal therapy. The patients were divided into two groups (n = 30) according to the rotary instrument used during root canal preparation (group A [HEDM] and group B [WOG]). Pain was evaluated after endodontic therapy at 8, 24, and 48 h intervals using the visual analog scale (VAS). Data obtained were analyzed using the chi-square test, independent t-test, MannWhitney U test, and Wilcoxon matched-pairs test.

Results

Statistically significant differences were observed between the two groups (P < 0.001) at 8, 24, and 48 h, with WOG exhibiting less pain than HEDM files.

Conclusion

Postoperative pain was lower in the WOG file system than in the HEDM file system after single-visit root canal therapy at 8, 24, and 48 h.

Effect of Different Treatment Regimen and Types of Endodontic Sealers on Pain and Periapical Radiographic Changes

INTRODUCTION: The study aims as a pilot study to evaluate the effect of different treatment regimen and different types of endodontic sealers on pain and periapical radiographic changes was studied. MATERIALS AND METHODS: Forty patients in need of an endodontic root canal treatment on anterior teeth were selected and divided into two groups (20 patients each), according to the endodontic treatment protocol (single or multiple visits). Then, each group was subdivided into two subgroups according to sealer used 10 each (AH Plus Jet resin sealer, Total Fill Bioceramic Sealer). To record pain intensity of the patients at different intervals: 1, 2, 3, 7 days, a visual analog scale was used. Furthermore, patients were recalled after 1, 3, 6, 9 months to evaluate periapical radiographic changes. RESULTS: Showed that as regard pain assessment both tested endodontic sealers, as well as single or multiple visits have no statistically significant difference between pain values of patients during all the observation period from immediately post-operative, after 4, 12, 24, 48, 72 h as well as after 7 days (p > 0.05). As regard lamina dura thickness, results showed that with both tested endodontic sealers as well as single or multiple visits, there was no statistically significant difference between lamina dura thickness of patients after 1 month, 3, 6 as well as after 9 months. CONCLUSIONS: Neither number of visits of endodontic treatment nor type of sealer used for obturation affects post-operative pain and thickness of lamina dura.

The influence of different NiTi instrumentation techniques on postoperative pain after single-visit root canal treatment

This study aimed to evaluate the effect of multi-file rotary (Protaper Universal) and reciprocating single-file (Reciproc Blue) root canal preparation techniques on the occurrence of postoperative pain in asymptomatic mandibular molar teeth with large periapical lesions in single-visit root canal treatment (RCT). A hundred and twenty teeth were randomly assigned to two groups: Protaper Universal (PTU) or Reciproc Blue (RB) instruments. Postoperative pain at 6, 12, 24, 48, 72 h and 7 days after obturation was measured. Mann-Whitney U-test was performed to compare the pain scores between the groups and to assess the relation of pain with patients' age and gender. Spearman's rank correlation was utilized to correlate the pain intensity and analgesic intake at different time points. There was no significant difference between the instrumentation techniques regarding postoperative pain at any time points evaluated (P > 0.05). There was a correlation between analgesic intake and intensity of pain (P < 0.05). No statistically significant difference was found among the groups assessed in the study in terms of analgesic intake (P > 0.05).

Postoperative Pain after Use of the WaveOne Gold and XP-endo Shaper Systems: A Randomized Clinical Trial

INTRODUCTION

The present study aimed to clinically compare the incidence of postoperative pain after endodontic treatment of posterior teeth using the WaveOne Gold (WOG; Dentsply Sirona, Ballaigues, Switzerland) and XP-endo Shaper (XPES; FKG Dentaire, La Chaux-de-Fonds, Switzerland) systems.

METHODS

In a single-blind randomized clinical trial, 148 vital teeth with an indication for conventional endodontic therapy for prosthetic purposes were treated by 5 specialists following a preestablished protocol. All participants were unaware of the treatment they received. The teeth were randomly divided into 2 groups (n = 74) according to the instrumentation system used (the WOG group and XPES group). The treatments were performed in a single session. The participants were asked to rate the intensity of postoperative pain on a visual analog scale (no pain, mild pain, moderate pain, and severe pain) after 24, 48, and 72 hours and 7 days.

RESULTS

The incidence of postoperative pain was higher in the XPES group after 24, 48, and 72 hours compared with those in the WOG group (P < .05). Two participants in the WOG group experienced severe postoperative pain after 24 hours. None of the participants in either group reported pain after 7 days (P > .05, Mann-Whitney test).

CONCLUSIONS

Postoperative pain is expected after preparation of the root canal system with the WOG and XPES systems tested, but it only persists for a short period. Although more common after the use of the XPES system, the pain was classified as mild at all time points.

Influence of the type of reciprocating motion on the cyclic fatigue resistance of reciprocating files in a dynamic model

Background

The aim of this study was to compare the influence of two novel reciprocating movements on the cyclic fatigue resistance of endodontic reciprocating files.

Methods

30 Procodile® (Komet Medical, Lemgo, Germany) files were selected in this study and distributed according to the following study groups depending on the movements to be performed: ReFlex Dynamic (n = 10), ReFlex Smart (n = 10) and Reciproc (n = 10) reciprocating movement. These files were fixed to a specific dynamic cyclic fatigue device designed and manufactured by 3D impression to simulate the pecking motion performed by the operator. The time to failure and the number of cycles of in-and-out of the endodontic files was registered. The results were analyzed by ANOVA and Weibull statistics.

Results

Statistically significant differences were found when the number of cycles of in-and-out movement and the time to failure of ReFlex Dynamic and Reciproc reciprocating movement (p < 0.001) and between ReFlex Smart and Reciproc reciprocating movement (p < 0.001) were compared in pairs. However, no statistically significant differences were observed between time to failure and number of cycles of in-and-out movement of ReFlex Dynamic and ReFlex Smart reciprocating movement (p = 0.253).

Conclusions

The ReFlex Smart reciprocating movement increased the cyclic fatigue resistance of endodontic reciprocating files compared with traditional reciprocating movement.

Effect of XP-endo Shaper versus conventional rotary files on postoperative pain and bacterial reduction in oval canals with necrotic pulps: a randomized clinical study

AIM

To assess postoperative pain and bacterial reduction following the use of XP-endo Shaper versus conventional rotary files in preparation of oval canals with necrotic pulps.

METHODOLOGY

This superiority, parallel, randomized, double blinded clinical trial was conducted in the clinic of the Endodontic Department, Faculty of Dentistry, Cairo University, Egypt. Sixty single-canalled mandibular premolars with necrotic pulps were randomly assigned into two equal groups. Canals were instrumented using XP-endo Shaper files in the intervention group and iRaCe rotary files in the control group. Bacterial samples were taken before and after canal instrumentation. Incidence and severity of postoperative pain was assessed using a modified VAS after 6, 12, 24 h and daily for 5 days. A culture method was used to assess the number of bacterial colony forming units. Incidence of analgesic intake as well as flare-ups was recorded. Data were analysed using chi-square, Fisher Exact, Mann-Whitney, Independent t-test, and Spearman's correlation for pain and bacterial counts.

RESULTS

The XP-endo Shaper compared with the iRaCe group was associated with a significantly lower incidence of postoperative pain at 6, 12, and 24 h (P = 0.039, 0.047, and 0.026, respectively), and severity of postoperative pain at 6 h (mean difference: 1.33, 95% CI: 0.307-2.352, P = 0.02), 12 h (mean difference: 1.1, 95% CI: 0.26-1.936, P = 0.007), 24 h (mean difference: 0.94, 95% CI: 0.178-1.701, P = 0.008) and 48 h (mean difference: 0.97, 95% CI: 0.192-1.747, P = 0.038). There was a significant decrease in bacterial count following canal instrumentation in both groups (P < 0.001) with no significant difference between them (mean difference: 0.83 × 10⁵ , 95% CI: 0.336 × 10⁵ -1.996 × 10⁵ , P = 0.56). A weak correlation existed between postoperative pain severity and bacterial counts (P = 0.54). There was no significant difference in analgesic intake between the two groups (P = 0.085). Flare-ups occurred in 3.3% of teeth in the iRaCe group, while no flare-ups occurred in the XP-endo Shaper group.

CONCLUSIONS

XP-endo Shaper was associated with a significantly lower frequency of postoperative pain for up to 24 h, and lower severity of postoperative pain for up to 48 h compared with iRaCe files. Both systems were equally effective in bacterial reduction from oval root canals with necrotic pulps.

Effect of Rotary and Reciprocating Instrumentation Motions on Postoperative Pain Incidence in Non-Surgical Endodontic Treatments: A Systematic Review and Meta-Analysis

OBJECTIVE

A systematic review and meta-analysis were conducted to determine whether there are postoperative pain differences resulting from rotary and reciprocation engine-driven instrumentation motions in non-surgical endodontic treatment or retreatment at 12, 24, and 48 hours.

METHODS

Four electronic databases (PubMed, Embase, Cochrane Library, and Scopus) were searched to identify randomised controlled trials that compared the effects of rotary and reciprocating instrumentation motions on postoperative pain. Two authors independently screened the search results, extracted the data, and assessed the quality using the Cochrane risk of bias tool. Due to numerous variables across studies, the random effect inverse variance method for meta-analysis was applied. When significant heterogeneity among studies was present, the random effects multi-variable meta-regression analysis was performed to determine the source of heterogeneity.

RESULTS

At all time intervals, the incidence of postoperative pain was higher in the reciprocating instrumentation group, but was not statistically significant. There was no significant difference in the analgesic intake between groups. Meta-regression analysis determined study population sizes as a significant heterogeneous factor, while significance was not observed for preoperative pain or the pulpal diagnosis.

CONCLUSION

There was no difference in postoperative pain at 12, 24, and 48 hours after non-surgical root canal treatment and retreatment, using reciprocating or rotary instrumentation motions.

Effect of Reciprocating and Rotary Systems on Postoperative Pain: A Systematic Review and Meta-Analysis

Introduction

Our study aimed to compare the incidence and intensity of postoperative pain after endodontic instrumentation with reciprocating and rotary systems.

Methods and Materials

An electronic literature search was performed with MEDLINE via PubMed, Scopus, and Web of Science databases from January 2008 to June 2020. Two high-impact endodontic journals were also hand searched. The selection criteria were: 1) Population; patients requiring endodontic treatment (primary or secondary), 2) Intervention and Comparison; endodontic instrumentation with reciprocating versus rotary systems, and 3) Outcome; postoperative pain. We extrapolated all included research data and reported them as dichotomized ordinal variables to evaluate the incidence of pain and continuous variables to assess pain intensity. Standardized mean difference (SMD) was calculated with Inverse Variance method for pain intensity; the incidence of postoperative pain was calculated using relative risk (RR) with the Mantel-Haenszel method. Random-effects model and 95% confidence interval (CI) were used for all meta-analyses. The I2 statistic was used to evaluate the statistical heterogeneity among studies (P<0.05).

Results

Twenty-one articles were selected and 17 of them were included in the meta-analysis for the evaluation of postoperative pain in the first 24 h. The meta-analysis was performed in two steps: a) all studies were included; b) subsequently studies with preoperative pain were excluded. A significant difference was observed in the intensity of postoperative pain; with rotary system having more favorable in both steps [a) SMD: 0.27; 95% CI: 0.13 to 0.41; P=0.0002; b) SMD: 0.37; 95% CI: 0.15 to 0.58; P=0.0010]. There was no significant difference in the incidence of pain, and the incidence of mild, moderate and severe pain (P>0.05).

Conclusion

The meta-analysis results revealed that rotary system were the instrument of choice as they had lower intensity of postoperative pain. Further controlled studies are advocated to provide clarification for intensity/incidence of postoperative pain in endodontic treatment with mechanized instruments.

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].

The Effect of Reciprocating and Rotary Systems on Postoperative Endodontic Pain: A Systematic Review and Meta-analysis

Introduction

The objective of this study was to evaluate the influence of the instrumentation kinematics on endodontic postoperative pain.

Methods and Materials

PubMed, Scopus, Web of Science, Lilacs, Cochrane Library and the System for Information on Gray Literature in Europe were searched electronically without time or language limitations up to June 2020. Subsequently, data extraction, quality assessment and meta-analysis were conducted. The meta-analysis was performed using random-effects inverse-variance methods, and heterogeneity was tested using the I 2 index (P<0.05).

Results

A total of 318 articles were successfully identified in the search. Sixteen studies were used in qualitative synthesis and fourteen used for quantitative synthesis. Meta-analysis showed that patients treated with reciprocating system had lower risk of pain 48 h after endodontic treatment (Risk ratio [RR]=1.04, 95% Confidence interval [CI]=1.01-1.06, P=0.003) (I2=0%), but the mean postoperative pain for the reciprocating system was greater 24 h post endodontic treatment (Standardized mean difference [SMD]=0.25, 95% CI=0.06 to 0.44, P=0.01) (I2=43%). Other time points presented similar rates of postoperative pain (P>0.05). The certainty of evidence ranges from very low to high.

Conclusions

The rate of postoperative endodontic pain was low, and reciprocating systems evoked more pain within the 24 h interval. Overall, the incidence and level of postoperative pain did not vary between reciprocating and rotary systems. There is no consensus if there is a relationship between the kinematics (rotary and reciprocating) and the incidence of postoperative pain.