Efficacy of 3 Different Irrigation Systems on Removal of Calcium Hydroxide from the Root Canal: A Scanning Electron Microscopic Study

The efficacy of three passive ultrasonic irrigation systems on intracanal medicament removal in a novel standardised three-dimensionally printed model

This study compared the efficacy of several passive ultrasonic irrigation (PUI) systems in removing intracanal medicament using 3-dimensionally printed root canal model assembled with dentin specimen. After the placement of the model in the agar container (37°C), the intracanal medicament was removed using three different PUI instruments including CK file, Irrisafe and Endosonic Blue. Then, the area coated by the medicament and the volumetric percentage of the remaining medicament was measured. Irrisafe and Endosonic Blue showed higher removal efficacy than CK and the control regarding both the coated area and remaining volume (p < 0.05). CK showed the lowest efficacy among the tested PUI systems (p > 0.05). Notably, Endosonic Blue group showed the smallest coated area among the tested groups (p < 0.05). Conclusively, PUI systems made of nickel-titanium alloy with small dimensions, such as Endosonic Blue, have advantages for the removal of intracanal medicaments from curved root canals.

Efficacy of Three Irrigation Methods in Removing Calcium Hydroxide from Curved Root Canals: An In Vitro Micro-CT Study

Aims and Objectives

This in vitro study aimed to compare the efficacy of three different irrigation methods in removing calcium hydroxide from curved root canals and to estimate the amount of residual medicament using microcomputed tomography.

Materials and Methods

Thirty extracted molars with curved mesial root canals, ranging from 25° to 30°, were prepared with ProTaper Next using X2 to full working length and were filled with calcium hydroxide. Teeth also were randomly divided into four groups: group 1 (n = 8)- Erbium: Yttrium-Aluminum-Garnet (Er:YAG) laser; group 2 (n = 8)-EndoActivator; group 3 (n = 8)-EndoVac; and a control group (n = 6)-negative control with no calcium hydroxide. Microcomputed tomography was used to evaluate the residual amount of filling material. Statistical analysis was performed using IBM SPSS Statistics 26, with a significance level of 0.05. Descriptive statistics, student t test, and Chi-square test were applied for data analysis.

Results

The greatest amount of residual calcium hydroxide was observed in the samples with EndoVac irrigation (0.515 mm3), followed by EndoActivator (0.381 mm3) and Er:YAG laser (0.121 mm3). However, no statistically significant difference was observed between the groups. The greatest residual amount was observed in the apical third (0.419 mm3), followed by the middle (0.050 mm3) and the coronal (0.015 mm3).

Conclusions

No statistically significant differences were observed in the efficacy of the tested techniques for removing calcium hydroxide from curved root canals, whereas a significant difference was observed in the distribution of residual material depending on the technique used. The removal of the calcium hydroxide was more effective in the coronal and middle third of the canal. The greatest residual material was found in the apical portion of the root canal.

The Bond Strength of Root Canal Filling after Calcium Hydroxide Removal with a Simple Apical Negative Pressure Kit in Oval-Shaped Root Canal

Background

The aim of this study was to evaluate the effect of a simple irrigating device, which produced from the apical negative pressure concept, as a final irrigating method after calcium hydroxide (CH) medication on the bond strength of epoxy resin-based sealer in the oval-shaped root canal.

Methods

Forty-eight single-rooted premolars with oval-shaped canals were included in the study. The crown was decoronized and canal instrumented with Mtwo (VDW GmbH, Munich, Germany) up to size 40/04. The specimens were assigned to four groups according to the irrigation protocol after 1 week of CH medication: control group (no medication) and three experimental groups conventional needle irrigation (CNI), passive ultrasonic irrigation (PUI), and simple apical negative pressure kit (sANP). The teeth were obturated with a warm vertical technique using epoxy resin-based sealers. After 1 week, the roots were transversally sectioned at coronal, middle, and apical thirds. A push-out test was performed by a universal testing machine, and statistical analysis was performed using One-Way ANOVA with Duncan's post hoc test.

Results

The bond strength in the control group was significantly higher than the CNI group in all root canal thirds (P < 0.05). At coronal third, sANP showed lower bond strength than PUI group (P < 0.05). However, the bond strength of sANP group was comparable to the control group (P > 0.05) which was significantly higher than the PUI group at apical third (P < 0.05).

Conclusion

A sANP enhanced the bond strength of epoxy resin-based sealer in the apical third of CH-medicated root canal in the oval-shaped canal.

Assessing the Contact Angle Between Dentin Treated With Irrigation and Calcium Hydroxide and Root Canal Sealers

Background

The long-term use of calcium hydroxide, or Ca(OH)2, on dentin has been established in the literature. However, scarce data is available on dentin wettability with Ca(OH)2.

Aim

The present study was conducted to assess the outcomes of Ca(OH)2 use on the wettability of dentin following two and four weeks of using sealers of bioceramic (BC) and Tubli-Seal™ in the root canal.

Methods

In this study, 168 specimens were divided into 12 groups of 14 specimens each and were numbered from G1 to G12. G1-G6 groups were tested with Tubli-Seal. Sterile water irrigation was reserved for G1 for two weeks (14 days) followed by two minutes treatment with 6% sodium hypochlorite (NaOCl) chemical irrigation and 17% EDTA (10 ml). G2 and G3 were subjected to Ca(OH)2 (0.1 ml of UltraCal) for two weeks followed by 10ml sterile water irrigation for two minutes with chemical irrigation. G4 to G6 were given similar treatment for four weeks. G7-G12 were assessed for BC sealer similarly to G1-G6. Two and four weeks of incubation with sterile water or Ca(OH)2 was done in 100% humidity at 37°C. SEM and EDX were done to evaluate the surface morphology of G1 and G6, and results were formed. 

Results

Significantly smaller contact angles were seen for Tubli-Seal (G1 to G6) compared to BC (G7 to G12) with p<0.05. Application of water irrigants and Ca(OH)2 (in G2, G5, and G11) showed a smaller (p<0.05, statistically significant) contact angle compared to the use of chemical irrigation agents and Ca(OH)2 (in G3, G6, and G12) except for G8 and G9. Based on EDX and SEM, compared to the use of chemical irrigation with Ca(OH)2, higher remnants of Ca(OH)2 were seen in the water irrigation, whereas, no remnant was seen with chemical irrigants. 

Conclusion

Better dentin wettability is seen with Tubli-seal compared to BC sealer. A smaller contact angle between root canal sealers and dentin is seen in the remaining calcium hydroxide samples. Also, calcium hydroxide can be removed from the polished dentin surface with two minutes of irrigation with 17% EDTA and 6% NaOCl.

Sonic irrigation for removal of calcium hydroxide in the apical root canal: A micro-CT and light-coupled tracking analysis

Objective

This study aimed to evaluate the efficacy of three sonic irrigation systems for removal of calcium hydroxide dressing from the apical root canal.

Materials and methods

A total of 96 single-rooted teeth in three categories of root canal curvatures (straight: 0–5°, moderate: 6–20°, and severe: > 20°) were allocated to four groups: conventional needle irrigation, EndoActivator, EQ-S, and Vibringe. The root canals were instrumented using Protaper NEXT and filled with calcium hydroxide. After removal of calcium hydroxide, the remaining volume of calcium hydroxide was measured by micro-CT analysis. Data were compared among root canal curvatures and irrigation systems using the Kruskal-Wallis test and Mann-Whitney test (p < .05). The oscillating range of each irrigation system was measured using light-coupled motion tracking.

Results

The volumes of calcium hydroxide remaining in the canals with severe curvature were significantly higher than in those of straight curvature (p < .05). In the canals of moderate or severe curvature, EQ-S showed the highest removal percentage, followed by EndoActivator, Vibringe, and needle irrigation (p < .05). Light-coupled tracking showed the largest oscillating range in EQ-S (p < .05).

Conclusions

Sonically activated irrigation systems with a flexible tip can be beneficial for calcium hydroxide intracanal dressing removal in the curved apical canals.

Endodontic cement penetration after removal of calcium hydroxide dressing using XP-endo finisher

We aimed to evaluate the penetration of endodontic cement following the removal of calcium hydroxide (Ca(OH)2) dressing using the XP-endo Finisher in association with different irrigating solutions. Sixty premolars were instrumented and applied with a Ca(OH)2 dressing. To remove Ca(OH)2, the teeth were divided into six groups, each with a different volume of sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA), as well as solution stirring time with XP-endo Finisher (0, 30, and 60 sec). Root canals were filled using the lateral condensation technique. Fluorescein dye was added to the cement for microscopic laser scanning analysis. In the generated images, linear measurements were taken in micrometers, and their averages were calculated. To analyze the perimeter penetration ratio of the cement, the total perimeter of the canal and the segment of the total perimeter of the canal where the endodontic cement penetrated into the dentinal tubules were measured in micrometers. We found that using an XP-endo Finisher in irrigation was more effective than using a needle and syringe during the extension and penetration of endodontic cement. Shaking with XP-endo Finisher with 17% EDTA increased the extent and perimeter of the penetration of the endodontic cement into the dentinal tubules. However, using the XP-endo Finisher with EDTA only was more efficient than using the instrument interchangeably in NaOCl and EDTA. Although XP-endo Finisher contributes to the removal of Ca(OH)2, none of the protocols or instruments used removed all Ca(OH)2 from the root system.

Evaluation of the effect of calcium hydroxide paste on sealer penetration into dentinal tubules by confocal laser scanning microscopy

The study evaluated sealer penetration after calcium hydroxide (Ca(OH)₂ ) removal from the root canals. Sixty single-rooted mandibular premolars were divided into six groups. Ca(OH)₂ paste placed into the root canals except for the control group (CG) was removed using the following irrigation techniques: conventional needle irrigation (CNI), EndoActivator (EA), EndoVac (EV), passive ultrasonic irrigation (PUI) and photon-induced photoacoustic streaming (PIPS) technique. After canal filling, the penetration depth, penetration area and penetration percentage of the sealer were determined using confocal microscopy. The CG and EA had a greater penetration depth than CNI in the middle section. The CG exhibited a higher dentinal tubule penetration area than CNI, EV and PUI in the middle section. EA was significantly more effective than PUI in the coronal section for the percentage of sealer penetration. EA and PIPS removed Ca(OH)₂ from root canals effectively because they presented similar penetration to the CG in all sections.

Comparison of the Efficacy of K-File, Canal Brush Technique, and Sonic Irrigation Technique in the Retrievability of Calcium Hydroxide and Metapex Intracanal Medicaments from Root Canals: An In vitro Cone-Beam Computed Tomography Analysis

Background and Objectives:

At present, none of the routinely used irrigating agents and activation techniques were able to completely remove the Ca(OH)₂ intracanal medicament placed inside the root canal system during endodontic therapy. With this as the background, the aim of this study was to achieve complete removal of Ca(OH)₂ when mixed with two different vehicles, using various irrigant activation techniques such as K-file, canal brush technique, and sonic irrigation technique, from the root canals of extracted human teeth.

Materials and Methods:

Seventy-two mandibular premolar teeth with straight single root canal were selected and filled either with oil-based Metapex or calcium hydroxide powder mixed with distilled water and were activated using different activation techniques such as K-file, canal brush, and sonic MM1500 and NaOCl alone. Volumetric analysis was performed utilizing cone-beam computed tomography.

Results:

None of the irrigants used were able to completely remove Ca(OH)₂ from root canal. Sonic MM1500 showed significant removal efficacy than K-file, canal brush technique, and NaOCl for both aqueous-based and oil-based calcium hydroxide.

Conclusion:

Sonic MM1500 performed better than K-file, canal brush technique, and NaOCl in removing both Metapex and Ca(OH)₂ powder. Regardless of the vehicles and agitation technique used, the remnants of Ca(OH)₂ were present on all thirds of the canal walls.

Effectiveness of XP-Endo Finisher and passive ultrasonic irrigation on intracanal medicament removal from root canals: a systematic review and meta-analysis

Background

XP-Endo Finisher (XPF) and passive ultrasonic irrigation (PUI) are commonly used in intracanal medicament removal. The effectiveness of these two techniques needs to be compared, and evidence-based research should be conducted.

Methods

A comprehensive literature search was conducted in PubMed, Web of Science, Embase, Cochrane Library, and Google Scholar up to December 20th, 2020. The outcomes of the included trials were pooled into the Cochrane Collaboration’s Review Manager 5.3 software. Cochrane’s risk-of-bias tool 2.0 was applied to assess the risk of bias.

Results

Nine articles were included in this systematic review and processed for data extraction, and eight studies were identified for meta-analysis. In general, the use of PUI showed better medicament removal effectiveness than XPF (odds ratio [OR]: 3.09; 95% confidence interval [CI], 1.96–4.86; P < 0.001). PUI was also significantly more efficient than XPF in the apical third (OR: 3.42; 95% CI, 1.32–8.84; P = 0.01). For trials using sodium hypochlorite (NaOCl) alone, PUI was also significantly more effective than XPF on intracanal medicaments removal (OR: 5.23; 95% CI, 2.79–9.82; P < 0.001). However, there was no significant difference between PUI and XPF when NaOCl and ethylenediaminetetraacetic acid (EDTA) were used in combination (OR: 1.51; 95% CI, 0.74–3.09; P = 0.26). In addition, for studies whose intracanal medicament periods were two weeks, the effectiveness of PUI was statistically better than the XPF (OR: 7.73; 95% CI, 3.71–16.07; P < 0.001). Nevertheless, for trials whose intracanal medicament time was one week or over two weeks, no differences between the XPF and PUI were found (OR: 1.54; 95% CI, 0.74–3.22; P = 0.25) (OR: 1.42; 95% CI, 0.44–4.61; P = 0.56).

Conclusions

The meta-analysis is the first study to quantitatively compare the effectiveness of XPF and PUI techniques on intracanal medicaments removal. With rigorous eligibility criteria, the study only included high-quality randomised controlled trials. The study indicated that PUI might be superior over XPF techniques for removing intracanal medicaments from artificial standardized grooves and cavities in the root canal system. The anatomical areas, irrigation protocol, and intracanal medicaments time may influence the cleaning efficacy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01644-7.

Effect of various calcium hydroxide removal protocols on the dislodgement resistance of biodentine in an experimental apexification model

Background/purpose

Residual calcium hydroxide (CH) in the root canal dentine walls may influence the adhesion of tricalcium silicate-based materials. The aim of this study is to evaluate the effect of various CH removal protocols on the dislodgement resistance of biodentine from simulated immature root canals in an experimental apexification model.

Materials and methods

CH was applied to 120 simulated immature root canals. The samples were divided into 12 experimental groups (n = 10) according to the applied irrigation protocols used for the removal of CH: Group 1: Sodium hypochlorite (NaOCl), Conventional needle irrigation (CNI); Group 2: NaOCl, EndoActivator; Group 3: NaOCl, XP-endo Finisher; Group 4: NaOCl- Ethylenediaminetetraacetic acid (EDTA), CNI; Group 5: NaOCl-EDTA, EndoActivator; Group 6: NaOCl-EDTA, XP-Endo Finisher; Group 7: NaOCl+etidronic acid (HEBP), CNI; Group 8: NaOCl+HEBP, EndoActivator; Group 9: NaOCl+HEBP, XP-endo Finisher; Group 10: NaOCl- Peracetic acid (PAA), CNI; Group 11: NaOCl-PAA, EndoActivator; Group 12: NaOCl-PAA, XP-endo Finisher; Control Group: CH was not applied. Biodentine was placed at the apical thirds of 130 immature root canals. Vertical loading was applied to biodentine fillings inside the dentin discs. Maximum force to dislodge the material was statistically analyzed with ANOVA.

Results

The control, NaOCl+HEBP (CNI, EndoActivator, XP-endo Finisher) and NaOCl-PAA (EndoActivator, XP-endo Finisher) groups exhibited the lowest dislodgement resistance values (p < 0.001). When used CNI, irrigation with NaOCl+HEBP resulted in lower resistance to dislodgement of biodentine compared to NaOCl, and NaOCl-EDTA (p < 0.001).

Conclusion

Adhesion of apical barrier materials to root canal dentine can be influenced by the irrigation protocols used for CH removal.

Final Endodontic Irrigation with 70% Ethanol Enhanced Calcium Hydroxide Removal from the Apical Third

INTRODUCTION

The purpose of this study was to evaluate the cleanliness of root canal walls and dentinal tubules after attempting to remove the calcium hydroxide dressing with different irrigant solutions and the use of nonactivated irrigation or passive ultrasonic irrigation (PUI).

METHODS

After root canal instrumentation, 80 single-rooted teeth were filled with calcium hydroxide mixed with propylene glycol and 0.1% rhodamine B dye and inserted into canals with a Lentulo spiral. The calcium hydroxide dressing was initially removed with 10 mL saline solution and reinstrumentation with the master apical file. Then, the samples were randomly assigned into 8 experimental groups (n = 10) according to the irrigant solution with or without PUI: 2.5% sodium hypochlorite, 17% ethylenediaminetetraacetic acid + 1.25% sodium lauryl ether sulfate (EDTA-T), 37% phosphoric acid, or 70% ethanol. A final flush with 5 mL saline solution was performed. The percentage of clean root canal walls and the depth of clean dentinal tubules were measured with images of confocal laser scanning microscopy. The groups were compared using the 2-way analysis of variance test with the Bonferroni post hoc test for depth analysis and the Kruskal-Wallis with Dunn post hoc test for the perimeter analysis.

RESULTS

Irrigation with 70% ethanol presented a significantly higher percentage of clean root canal walls and a higher depth of clean dentinal tubules when compared with irrigation with 2.5% sodium hypochlorite and 17% EDTA-T for both irrigation methods (P < .05). No differences were observed between nonactivated irrigation or PUI protocols (P > .05).

CONCLUSIONS

Seventy percent ethanol enhanced calcium hydroxide removal from the apical root third compared with 2.5% sodium hypochlorite or 17% EDTA-T.

Evaluation of different irrigation solutions and activation methods on removing calcium hydroxide

Background/purpose

Dual Rinse HEDP is a soft chelator which can be used simultaneously with sodium hypochlorite (NaOCl). The aim of this study is to evaluate the efficacy of Dual Rinse HEDP with different irrigation systems on removing calcium hydroxide [Ca(OH)₂].

Materials and methods

Eighty maxillary central incisor teeth were shaped and a standard groove on the apical third of the root canal surface was prepared. The root canals were filled with Ca(OH)₂. Samples were divided into two groups according to the solution and these two groups were divided into three subgroups based on the activation technique. In group 1 (n = 10) Ca(OH)₂ was removed using conventional irrigation with NaOCl whereas in group 2 (n = 10) conventional irrigation with NaOCl - Dual Rinse HEDP mixture was used. Group 3 (n = 15) and group 4 (n = 15) received sonic activation with the same irrigants as groups 1 and 2 respectively. In group 5 (n = 15) passive ultrasonic irrigation (PUI) was used with NaOCl while in group 6 (n = 15) the irrigant was the mixture. The amount of remaining Ca(OH)₂ in the artificial grooves were evaluated under a light microscope.

Results

None of the procedures managed to completely remove the Ca(OH)₂ from artificial grooves. There was no significant difference between the groups (p = 0.053). The scores were significantly lower in PUI group compared to the other techniques between NaOCl groups (p = 0.021).

Conclusion

Dual Rinse HEDP does not make a difference on elimination of Ca(OH)₂. PUI is more efficient than both methods when NaOCl solution is used.

Effect of calcium hydroxide mixed with lidocaine hydrochloride on postoperative pain in teeth with irreversible pulpitis and symptomatic apical periodontitis: a preliminary randomized controlled prospective clinical trial

OBJECTIVES

To investigate the effect of calcium hydroxide mixed with lidocaine HCl on postoperative spontaneous pain.

MATERIALS AND METHODS

Sixty patients having irreversible pulpitis and symptomatic apical periodontitis with a preoperative spontaneous pain and percussion pain which was more than 50 on a visual analogue scale (100 mm VAS) were included in this study. After the preparation of the root canals, the patients were randomly distributed into two groups according to the calcium hydroxide vehicle, control group (mixed with saline) and calcium hydroxide mixed with lidocaine HCl (n = 30). Postoperative spontaneous pain scores were recorded by a VAS every day for a week. Data were analysed using one-way analysis of variance, chi-squared test and Mann-Whitney U tests (p = 0.05).

RESULTS

The calcium hydroxide mixed with lidocaine HCl group resulted in significantly less pain compared with the calcium hydroxide mixed with saline group during days 1 to 4 (p < 0.05). There were no significant differences between the groups in terms of postoperative percussion pain levels (p > 0.05).

CONCLUSION

Within the limitations of this study, it can be concluded that the calcium hydroxide mixed with lidocaine HCl can be beneficial in reducing postoperative pain in teeth with irreversible pulpitis and symptomatic apical periodontitis.

CLINICAL RELEVANCE

The calcium hydroxide mixed with lidocaine HCl can be beneficial in reducing postoperative pain in teeth with irreversible pulpitis and symptomatic apical periodontitis.

CLINICAL REGISTRATION NUMBER

TCTR20181121003.

Calcium Silicate-Based Cements as Root Canal Medicament

Purpose

This study aims to retard the setting reaction of CSC by mixing it with 2% chlorhexidine gel (CHX) which will be used as an intracanal medicament, and to evaluate the removal of the experimental medicaments from the root canal.

Materials and Methods

White Portland cement, white ProRoot MTA and Biodentine were mixed with 2% CHX. The setting time, flowability and film thickness of the CSC/CHX mixture (experimental medicaments) were assessed and measured following the standards of ISO specification. Calcium ion release was measured using ICP-OES, while pH was tested using a pH meter. Moreover, twenty single-rooted teeth were filled with the experimental medicaments for seven days, then the medicaments were removed and the samples analyzed using SEM. Calcium hydroxide paste was used as a control.

Results

The setting time of the experimental medicaments was inhibited until 84 days. The calcium ion release of the experimental medicaments was significantly higher compared to the control over the period of 14 days (P<0.001). The mean pH value was above 11.45 for all tested materials over a period of 14 days, with no significant difference between them (P<0.05). There was no significant difference in film thickness of the experimental medicaments compared to the control (P> 0.05). However, the flowability of the experimental medicaments was significantly higher than the control (P<0.05). SEM showed no significant differences in the removal of the intracanal medicaments between all the tested groups.

Conclusion

The addition of 2% CHX to CSCs retarded or inhibited its setting reaction over a period of 84 days. The calcium ion release and flowability of these experimental medicaments was found to be better than calcium hydroxide. Removal of the intracanal medicaments from the root canal was successfully achieved in all groups. Therefore, these experimental medicaments have the potential to be used as an enhanced root canal medicament.

The efficacy of different irrigation protocols in removing tricalcium silicate-based sealers from simulated root canal irregularities

OBJECTIVE

The aim of this study was to evaluate the efficacy of different irrigation protocols in removing two tricalcium silicate-based sealers from simulated root canal irregularities and root canal walls.

MATERIAL AND METHODS

Root canals of 140 single-rooted teeth were instrumented. In one-half of each root, an apical groove was created. The samples were divided into two main groups (n = 70) based on the sealer used. In group 1, the grooves were filled with MTA Fillapex; in group 2, BioRoot RCS. The reassembled root halves were divided into six experimental and one control groups: 2.5% NaOCl-17% EDTA (Passive ultrasonic irrigation [PUI]), 5% NaOCl/9% DualRinse HEDP (PUI), 2.5% NaOCl-7% Maleic acid (PUI), 2.5% NaOCl-17% EDTA (Er:YAG laser activated irrigation [LAI]), 2.5% NaOCl/9% DualRinse HEDP (LAI), 2.5% NaOCl-7% Maleic acid (LAI), Distilled water (Control). Specimens were scored using SEM. The data were analysed using Kruskal-Wallis and Mann Whitney U tests.

RESULTS

Maleic acid and DualRinse HEDP removed higher amounts of MTA Fillapex from the grooves compared to EDTA, when used with both activation methods (p < .001).

CONCLUSIONS

Ultrasonically activated maleic acid or DualRinse HEDP can be an effective irrigation regimen in removing tricalcium silicate-based sealers.

Efficacy of Removal of Calcium Hydroxide Medicament from Root Canals by Endoactivator and Endovac Irrigation Techniques: A Systematic Review of In vitro Studies

Introduction:

The aim of this systematic review was to systematically evaluate and summarize the outcomes of in vitro studies comparing Endoactivator irrigation and Endovac irrigation techniques for removing calcium hydroxide (Ca[OH]₂) medicament from the root canals.

Materials and Methods:

The research question was developed according to the population, intervention, comparison, and outcome strategy. A computerized literature search was conducted in Medline, PubMed, Google Scholar, and Embase. A hand search of the reference lists of identified articles was performed to separate relevant articles. Two reviewers critically assessed the studies that fulfilled the inclusion criteria and processed. Evaluation of the risk of bias of the studies was performed independently by the two reviewers.

Results:

After study selection, 61 were assessed for eligibility. Of these, 13 met the inclusion criteria and were included in the systematic review. Since significant heterogeneity was found in the methodologies, it was not possible to conduct a meta-analysis.

Conclusions:

On the basis of available evidence, we determined that Endoactivator irrigation technique showed better performance in removing Ca(OH)₂ intracanal medicaments from middle third and coronal third area of the root canals and Endovac irrigation technique showed better performance from the apical third area of the root canals. Due to the limitations, small sample sizes, and low number of included studies, further research is needed to confirm our results.

Evaluating the efficacy of different techniques and irrigation solutions for removal of calcium hydroxide from the root canal system: A scanning electron microscope study

Aim:

The aim of this scanning electron microscope study was to compare the efficacy of two techniques (EndoVac and EndoActivator) and two irrigating solutions (5.25% NaOCl in combination with 17% ethylenediaminetetraacetic acid vs. Savlon™) for removal of calcium hydroxide (CH) from the root canal walls.

Settings and Design:

The study was carried out in the specialty of conservative dentistry and endodontics.

Materials and Methods:

Forty single-canal human teeth were used. The specimens were de-coronated to obtain a standardized root length of 15 mm using a diamond disk. The canals were instrumented till F3 ProTaper and CH intracanal medicament placed in the root canal. One week later, teeth were randomly divided into one control group and six experimental groups according to different irrigation protocols with different techniques.

Statistical Analysis:

Kruskal–Wallis test was conducted to analyze the effect of different treatment measures with respect to three regions of tooth.

Results:

The results indicated that there was no statistically significant difference between the two irrigation solutions and two techniques.

Conclusion:

To achieve the best adaptation of filling material after root canal treatment, it is crucial to remove intracanal medication from the root canal walls. However, none of the irrigation regimens and different techniques were able to completely remove the CH from the root canal wall.

Effectiveness of various irrigation protocols for the removal of calcium hydroxide from artificial standardized grooves

Objective

The aim of this study was to investigate the ability of laser-activated irrigation (LAI), XP-endo Finisher, CanalBrush, Vibringe, passive ultrasonic irrigation (PUI), and conventional syringe irrigation systems on the removal of calcium hydroxide (CH) from simulated root canal irregularities.

Material and Methods

The root canals of one hundred and five extracted single-rooted teeth were instrumented using Reciproc rotary files up to size R40. The teeth were split longitudinally. Two of the three standard grooves were created in the coronal and apical section of one segment, and another in the middle part of the second segment. The standardized grooves were filled with CH and the root halves were reassembled. After 14 days, the specimens were randomly divided into 7 experimental groups (n=15/group). CH was removed as follows: Group 1: beveled needle irrigation; Group 2: double side-vented needle irrigation; Group 3: CanalBrush; Group 4: XP-endo Finisher; Group 5: Vibringe; Group 6: PUI; Group 7: LAI. The amount of remaining CH in the grooves was scored under a stereomicroscope at 20× magnification. Statistical evaluation was performed using Kruskal–Wallis and Bonferroni-Correction Mann–Whitney U tests.

Results

Groups 1 and 2 were the least efficient in eliminating CH from the grooves. Groups 6 and 7 eliminated more CH than the other protocols; however, no significant differences were found between these two groups (P>.05).

Conclusions

Nevertheless, none of the investigated protocols were able to completely remove all CH from all three root regions. LAI and PUI showed less residual CH than the other protocols from artificial grooves.

Comparison of different irrigation and agitation methods for the removal of two types of calcium hydroxide medicaments from the root canal wall: an in-vitro study

Background and aim

Comparison of different irrigation and agitation methods for the removal of two types of calcium hydroxide medicaments from the root canal walls.

Methods

Fifty extracted single rooted teeth were selected for this study. After decoronation, the root canals of these teeth were prepared to the size F3 (30 no.) using rotary ProTaper file system. These samples were randomly divided into four groups. Group 1 (n=20) were filled completely with water based calcium hydroxide (CH), Group 2 (n=20) were filled with oil based CH using lentulo spiral, Group 3 (n=5) - the positive control group received the CH as intracanal medication, but no subsequent removal, Group 4 (n=5) - the negative control did not receive CH placement. Further on, Group 1 and Group 2 were divided into four sub-groups (n=5). In sub-group A we performed conventional syringe irrigation with side-vented needle sub-group B) manual dynamic agitation, sub-group C sonic agitation using endoactivator, sub-group D passive ultrasonic irrigation (PUI). Roots were split longitudinally into mesial and distal halves. Digital images of the root canal walls were acquired by a Dental Operating Microscope (DOM) and assessed by using a scoring criteria at different thirds (coronal, middle and apical) of the root canal as follows: score 1, score 2, score 3, and score 4. Data were analyzed applying one-way analysis of variance (ANOVA) and Tukey’s multiple comparison tests at a 95% confidence interval (P < 0.05).

Results

Statistically significant differences were not found between the experimental groups and the negative group in any one third of the root canal (P>0.05). However, a difference did exist between the experimental groups and the positive control group (P<0.05). None of the experimental groups totally removed CH substances from root canal walls.

Conclusion

Among all experimental groups, removal of CH was best achieved by sonic agitation using endoactivator followed by passive ultrasonic irrigation (PUI), manual dynamic agitation and conventional syringe irrigation with side-vented needle.

An in vitro study on the efficacy of removing calcium hydroxide from curved root canal systems in root canal therapy

To compare the efficacy of various irrigants (citric acid, ethylenediaminetetraacetic acid (EDTA) and NaOCl) and techniques in removing Ca(OH)₂ in two types of curved root canal systems, simulated root canals with specific curvatures were used to investigate the effects of different irrigants and instruments on Ca(OH)₂ removal. The optimal methods were verified on extracted human teeth. Simulated root canals were assigned to one of two groups based on the irrigation solution: 10% citric acid or 2.5% NaOCl. Each group was divided into four subgroups according to the technique used to remove Ca(OH)₂. The percentage of Ca(OH)₂ removal in different sections of root canals was calculated. On the basis of the results obtained for the simulated canals, 10% citric acid and 17% EDTA were applied to remove Ca(OH)₂ from the extracted human teeth with curved root canal systems. The teeth were scanned by micro computed tomography to calculate the percentage of Ca(OH)₂ removal in the canals. In simulated root canals, we found that 10% citric acid removed more Ca(OH)₂ than 2.5% NaOCl in the 0–1 mm group from the apex level (P<0.05). Ultrasonic and EndoActivator activation significantly removed more Ca(OH)₂ than a size 30 K file in the apical third (P<0.05). However, there were no significant differences in any sections of the canals for 10% citric acid or 17% EDTA in removing Ca(OH)₂ in extracted human teeth. We concluded that it was effective to remove residual Ca(OH)₂ using the decalcifying solution with EndoActivator or Passive Ultrasonic Irrigation in a curved root canal system. A protocol for Ca(OH)₂ removal was provided based on the conclusions of this study and the methods recommended in previous studies.

Effect of Intra-Canal Calcium Hydroxide Remnants on the Push-Out Bond Strength of Two Endodontic Sealers

INTRODUCTION

The aim of this study was to evaluate the effect of intra-canal calcium hydroxide (CH) remnants after ultrasonic irrigation and hand file removal on the push out bond strength of AH-26 and EndoSequence Bioceramic sealer (BC Sealer).

METHODS AND MATERIALS

A total of 102 single-rooted extracted human teeth were used in this study. After root canal preparation up to 35/0.04 Mtwo rotary file, all the specimens received CH dressing except for 34 specimens in the control group. After 1 week, the specimens with CH were divided into 2 groups (n=34) based on the CH removal technique; i.e. either with ultrasonic or with #35 hand file. Then specimens were divided into two subgroups according to the sealer used for root canal obturation: AH-26 or BC Sealer. After 7 days, 1 mm-thick disks were prepared from the middle portion of the specimens. The push out bond strength and failure mode were evaluated. Data were analyzed by the two-way ANOVA and Tukey's post hoc tests.

RESULTS

The push out bond strength of both sealers was lower in specimens receiving CH. These values were significantly higher when CH was removed by ultrasonic (P<0.05). The dominant mode of failure in all subgroups was of mixed type except for the BC Sealer specimens undergoing CH removal with hand file which dominantly exhibited adhesive mode of failure.

CONCLUSION

CH remnants had a negative effect on the push out bond strength of AH-26 and BC Sealer. Ultrasonic irrigation was more effective in removing CH.

Efficacy of XP-endo finisher files in the removal of calcium hydroxide paste from artificial standardized grooves in the apical third of oval root canals

AIM

To compare the efficacy of the XP-endo finisher file (XP) (FKG Dentaire, La Chaux de Fonds, Switzerland) to that of passive ultrasonic irrigation (PUI) and conventional syringe and needle irrigation (SNI) in the removal of calcium hydroxide paste from an artificial standardized groove in the apical third of root canals.

METHODOLOGY

The root canals of 68 mandibular incisors with single oval canals were prepared using Mtwo instruments (VDW GmbH, Munich, Germany) up to size 40, .04 taper. Each tooth was split longitudinally, and in one half of the root, a standardized groove was prepared in the apical part of the specimen. The grooves were filled with Ca(OH)₂ , and the root halves were reassembled. The roots were randomly divided into two control groups (n = 4) and three experimental groups (n = 20) according to the Ca(OH)₂ methods used: XP, PUI and SNI. The amount of remaining medicament was evaluated under X25 magnification using a 4-grade scoring system. Kappa values were calculated for intra- and interobserver agreement evaluation. The differences in the Ca(OH)₂ scores amongst the different groups were analysed using the Kruskal-Wallis test.

RESULTS

None of the tested methods could completely clean the Ca(OH)₂ from the artificial standardized groove in the apical third of the root canals. XP and PUI removed significantly more Ca(OH)₂ than SNI (P < 0.001), with no significant differences between them (P = 0.238).

CONCLUSIONS

XP and PUI were more effective in removing Ca(OH)₂ from artificial standardized grooves in the apical third of root canals than SNI.