The effect of two rotary and two reciprocating NiTi systems on postoperative pain after root canal retreatment on single-rooted incisor teeth: A randomized controlled trial

In vitro evaluation of filling material removal and apical debris extrusion after retreatment using Reciproc blue, Hyflex EDM and ProTaper retreatment files

OBJECTIVES

To evaluate the amount of remaining filing material and apical debris extrusion after retreatment using Reciproc Blue, Hyflex EDM and ProTaper Retreatment Files.

MATERIALS AND METHODS

Thirty-six extracted permanent mandibular first molars with moderately curved mesial roots were selected. Mesiobuccal canals were prepared using the ProTaper Next system up to size X2 and filled using gutta-percha and Adseal sealer via cold lateral compaction. Teeth were randomly divided into three equal groups (n = 12): Group 1: Reciproc Blue (RB)(VDW, Germany), Group 2: Hyflex EDM (HEDM)(Coltene/Whaledent, Switzerland), Group 3: ProTaper Universal Retreatment file system + ProTaper Next file system (PTUR + PTN)( Dentsply Maillefer, Switzerland). Eppendorf tubes were used to collect the apically extruded debris. Cone-beam computed tomographic scans were taken prior to and after retreatment and the volume of remaining filling material was assessed at the coronal, middle and apical levels. Statistical analysis was performed using the Kruskal-Wallis test, Friedman's test and Wilcoxon Sign Rank test. Significance level was set at p value 0.05.

RESULTS

There were no statistically significant differences among the three groups in the reduction of the volume of the filling material or in the amount of apically extruded debris.

CONCLUSION

All the tested filing systems showed similar efficacy in removing the filling material, however, none of them could achieve its complete removal. Apical extrusion of debris occurred with all the systems used with no significant difference between the three groups.

Prevalence of postoperative pain after endodontic treatment using low and high concentrations of sodium hypochlorite: a systematic review and meta-analysis

OBJECTIVES

To determine the prevalence of postoperative pain after endodontic treatment using low (LC) and high (HC) concentrations of sodium hypochlorite (NaOCl).

MATERIALS AND METHODS

Six databases and the grey literature were searched to identify randomized clinical trials that evaluated postoperative pain after endodontic treatment using NaOCl. NaOCl concentrations were dichotomized into 'LC' (0.5% to 3%) and 'HC' (≥ 5%) and a proportion meta-analysis was applied to determine the postoperative pain prevalence: overall and according to pain intensity and postoperative time. The prevalence of patients using pain control medication was also determined. A significance level of 5% and a random effect model were applied for data analysis. Between-study heterogeneity was assessed by I2 index. Risk of bias (RoB) was assessed using the Cochrane Risk-of-Bias 2.0 tool. The certainty of evidence was assessed using the GRADE approach.

RESULTS

Ten studies were included in the review and eight in the meta-analysis. The overall prevalence of postoperative pain was 45% in LC and 39% in HC. The prevalence of pain in LC and HC after 24 h was 25% and 40%, respectively. After 48 h, the prevalence decreased to 10% in LC and 25% in HC. 'Absent pain' was the most prevalent score. The prevalence of patients who used medication was 9% in LC and 15% in HC. Three studies were classified as 'high RoB', five as 'low RoB', and two as 'some concerns'. The certainty of evidence was very low.

CONCLUSIONS

The overall prevalence of postoperative pain after endodontic treatment using LC and HC of NaOCl was 45% and 39%, respectively.

CLINICAL RELEVANCE

Postoperative pain is common after endodontic treatment using NaOCl, but tends to decrease over time.

Evaluation of the rotary kinematics between actual and set speeds of X-Smart Plus, VDW.Silver and iRoot motors

The present study evaluated the actual rotational speed of three different endodontic motors compared to the values provided by the manufacturers. A total of three endodontic motors (X-Smart Plus, VDW.Silver, and iRoot) were tested at 400 rpm and 800 rpm and 2 N/cm2 torque. The kinematics of the devices was recorded by using a custom angle-measuring disc with a 50-mm diameter attached to the handpiece provided by the manufacturer, whereas their movement was captured by a high-speed camera at 2,400 frames per second, 800 x 800 pixel-resolution and distance of 0.3 m from the target object. Statistical analysis was performed at a significance level of 5%. At 400 rpm, the iRoot motor had a value of 17.94 rpm above that indicated by the manufacturer, which was significantly different from those of X-Smart Plus (5.20 rpm below that indicated by the manufacturer) and VDW.Silver (0.62 rpm above that indicated by the manufacturer) motors (P < 0.05). At 800 rpm, the iRoot motor had a value of 51.34 rpm below that indicated by the manufacturer, whereas the X-Smart Plus motor had a value of 13.00 rpm below that indicated by the manufacturer (P > 0.05). The VDW.Silver motor statistically differed from the iRoot and X-Smart Plus ones, showing a value of 1.68 rpm above that indicated by the manufacturer. In conclusion, the X-Smart Plus, VDW.Silver, and iRoot motors showed lower variations in the rotational speed values compared to those reported by their manufacturers. The endodontic motors presented different behaviors between them, with the VDW.Silver motor presents the most accurate values and the iRoot presents the most divergent values.

Effect of different retreatment files using different kinematics on the release of inflammatory mediators in root canal retreatment of single-rooted teeth: a randomized clinical trial

OBJECTIVES

This randomized clinical trial aimed to evaluate the effect of two rotaries (ProTaper Universal Retreatment (PTUR)), D-Race (DR) + XP-Endo Finisher R (XPFR) and one reciprocating (Reciproc Blue (RB) retreatment techniques on the release of neuropeptides (Substance P, calcitonin gene-related peptide (CGRP)), and cytokines (IL-6 and IL-10) in periapical fluid in root canal retreatment of single-rooted teeth.

MATERIALS AND METHODS

In this randomized clinical trial (ClinicalTrials.gov ID: NCT05039502), seventy-five patients scheduled for retreatment were randomly divided into 3 groups according to the file system used to remove root canal filling materials (n = 25): PTUR, RB, and DR + XPFR. After reshaping and disinfection of the root canals, periapical fluid samples were taken, and the levels of Substance P, CGRP, IL-6, and IL-10 were measured by enzyme-linked immunosorbent assay (ELISA) test. Data were analyzed using the Kruskal-Wallis and chi-square tests. The level of significance was set as p = 0. 05.

RESULTS

All the allocated participants received the intervention and were analyzed. There was no statistically significant difference among groups in terms of gender, age, tooth localization, and the distribution of analgesic use after treatment (p values 0.799, 0.095, 0.637, 1.000, respectively). No statistically significant difference was found in terms of the levels of Substance P, CGRP, and IL-10 among groups (p > .05), except IL-6.

CONCLUSIONS

PTUR, RB, and DR + XPFR files have comparable results in the expression of inflammatory mediators.

CLINICAL RELEVANCE

Retreatment files powered with rotary or reciprocating motion produced similar neuropeptide and cytokine levels in patients.

A Comparative Evaluation of the Apically Extruded Debris from Root Canals Prepared by R-Motion NiTi File System

Background

Apically extruded debris (AED) is an inherent concern during root canal treatment for both endodontists and general practitioners. The present study investigates the AED of the novel R-Motion single-file reciprocating system compared to standard single reciprocating and multifile rotary systems.

Materials and Methods

Fifty-six moderately curved palatal roots of upper maxillary first molars were selected for the present study. The samples were then divided randomly into four groups (n = 14)- Group I: R-motion (RM), Group II: WaveOne Gold (WOG), Group III: ProTaper Next (PTN), and Group IV: HyFlex EDM (HFEDM). The researcher has modified Myers and Montgomery's method to simulate human body temperature. Vials were used to collect debris and weighted using a 0.00001 sensitive balance before and after instrumentation. The instrumentation of all experimented groups was done at 37°C, terminated at master apical file #25. An auto syringe with a side vented needle was used to deliver 8 ml of deionized water for irrigation of each sample during preparation. Vials were stored in a dry sealed desiccator which contained CaSO₄ crystals, for 24 hr before weighing. The weight of the collected debris was obtained by subtracting the preinstrumentation weight from the postinstrumentation weight for each vial. The Kruskal-Wallis and Mann-Whitney U tests were performed to analyse the statistical difference in the amount of debris between the tested groups at a 0.05 significance level.

Results

The RM system produced less debris extrusion than all tested groups, with a significant difference between the former and the WOG and the PTN systems. However, WOG, PTN, and HFEDM showed no statistically significant difference in the amount of AED.

Conclusion

All tested groups produced apical debris in different amounts. The RM produced substantially less AED than WOG and PTN. Meanwhile, WOG, PTN, and HFEDM caused a comparable amount of AED.

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.