Effect of chlorhexidine digluconate on antimicrobial activity,cell viability and physicochemical properties of three endodontic sealers

ObjectiveAssess the biological and physicochemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) leachates with and without chlorhexidine (CHX).MethodsThe sealers were studied in no contact and 1-minute contact with CHX. For biological properties (antibacterial activity and cytotoxicity), leachates were formed in saline of freshly mixed, 1-, 7- and 28 days set sealers. The antibacterial properties of sealer leachates were investigated for planktonic and biofilm growth of E. faecalis, S. mutans, S.epidermidis and S.aureus. The 3-(4,5 dimethylthiazolyl-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to evaluate murine fibroblast cell viability after exposure to the leachates. The physical properties (water uptake, sorption, solubility, porosity, surface characteristics) of sealers and the pH of the immersion liquid (saline or distilled water) were also assessed over a 28-days period.ResultsCHX improved the antibacterial properties of the sealer leachates and reduced cell viability for all sealer leachates, except for freshly mixed PCS. BioRoot RCS leachates presented the highest antibacterial properties and cell viability with and without CHX contact. PCS was the material most affected by CHX in terms of physical properties, whereas for AH Plus, solubility was increased. CHX did not affect the physical properties of BioRoot RCS, except for solubility that was decreased. CHX contact did not change sealers’ alkalinity in distilled water whereas it increased it for AH Plus and BioRoot RCS in saline.SignificanceCHX improved the antibacterial efficacy of sealer leachates and either compromised or did not affect cell viability. CHX affected to various extent sealers’ physicochemical properties.     

Interfacial Characteristics and Cytocompatibility of Hydraulic Sealer Cements

Introduction

The stability and long-term success of root canal obturation depends on the choice of sealer because the sealer bonds to the dentin and stabilizes the solid cone. Furthermore, the sealer needs to be nontoxic because sealer toxicity will certainly lead to treatment failure. The aim of this study was to assess the sealer-dentin interface of 3 hydraulic root canal sealers and to evaluate their cytocompatibility compared with AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany).

Immediate and Long-Term Porosity of Calcium Silicate–Based Sealers

IntroductionOpen pores between endodontic sealer and root canal walls present potential niches for bacterial growth and migration pathways. The aim was to assess the internal and external porosity of calcium silicate–based sealers and to ascertain the long-term effect of storage in simulated body fluid on sealer porosity.MethodsSixteen single-rooted teeth were filled with gutta-percha and 1 of 4 root canal sealers: BioRoot RCS, EndoSequence BC, MTA Fillapex, or AH Plus. Obturated roots, stored in Hank's balanced salt solution, were scanned after 7 days and after 6 months by using micro–computed tomography at an isotropic resolution of 9.9 μm. Total, open, and closed porosity were calculated in the coronal, middle, and apical thirds. Data were statistically analyzed by using general linear model and paired t test (α = 0.05).ResultsSignificantly higher percentage of open than closed porosity was found in all groups. Initially, significantly greater open and total porosity were found for MTA Fillapex than for AH Plus. After 6 months, the percentage of open and total porosity increased in BioRoot RCS and MTA Fillapex and decreased in AH Plus and EndoSequence BC. Both initially and after storage, coronal region of all sealers had significantly greater total porosity than middle and apical regions, which were comparable.ConclusionsNone of the root fillings were void-free, with predominant open porosity persisting after long-term storage.     

Comparison of the antibacterial activity of calcium silicate- and epoxy resin-based endodontic sealers against Enterococcus faecalis biofilms: a confocal laser-scanning microscopy analysis

Odontology - This study assessed the antibacterial activity of BioRoot RCS in comparison with that of the Totalfill BC and AH Plus sealers against Enterococcus faecalis biofilms in dentinal tubules...     

Characterization of Leachates from 6 Root Canal Sealers

Introduction

The aim of this study was to evaluate 6 different endodontic sealers by characterizing their leachates and comparing their solubility in water over a 4-week period.

Antibacterial Activity of Endodontic Sealers against Planktonic Bacteria and Bacteria in Biofilms

Introduction

The aim of this study was to investigate the antibacterial activity of 4 endodontic sealers against bacteria planktonic grown or in biofilms commonly detected from persistent and secondary endodontic infections.

Cytokine Production and Cytotoxicity of Calcium Silicate–based Sealers in 2- and 3-dimensional Cell Culture Models

IntroductionThe aim of the present study was to assess the effects of different silicate-based sealers (ie, BioRoot RCS [Septodont, Saint Maur des Fosses, France], ProRoot ES [Dentsply Sirona, York, PA], and MTA Fillapex [Angelus, Londrina, PR, Brazil]) on cytokine production and viability of human periodontal ligament stem cells (PDLSCs). AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) was used as a reference material.MethodsPDLSCs were cultured either in 2-dimensional or 3-dimensional conditions (in 0.15%–0.5% PuraMatrix [BD Biosciences, Bedford, MA]) for 24 hours with eluates from set endodontic sealers. Additionally, the toxicity of eluates from endodontic sealers was evaluated using an in vitro root model experimental procedure. PDLSC viability was determined using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. PDLSC culture medium was used for cytokine quantification (interleukin [IL]-6, IL-8, growth-regulated oncogene, IL,-4 and IL-10) using the HCYTMAG-60K-PX41 Milliplex kit (EMD Millipore, Burlington, MA).ResultsIn 2-dimensional culture conditions, BioRoot RCS revealed a good PDLSC viability rate. ProRoot ES had no effect on PDLSC viability regardless of the dilution. MTA Fillapex was strongly cytotoxic even at the lowest extract dilutions (1:1, 1:2, and 1:4). Encapsulation of PDLSCs in PuraMatrix tended to decrease the cytotoxic effect of the sealers. In the 3-dimensional in vitro root model experimental procedure, BioRoot RCS, ProRoot ES, and MTA Fillapex revealed a cytocompatibility pattern. Different calcium silicate–based sealers exhibited different proinflammatory cytokine production. BioRoot RCS greatly stimulated the release of IL-10 and, to a lesser degree, IL-4 by PDLSCs (P < .05).ConclusionsBioRoot RCS and ProRoot ES did not induce proinflammatory cytokines and promoted anti-inflammatory cytokine secretion by PDLSCs that may have a positive local impact by attenuating an initial inflammatory response.     

Drug-Silica Coassembled Particles Improve Antimicrobial Properties of Endodontic Sealers

IntroductionThe purpose of this study was to assess the antimicrobial activity and flow of root canal sealers after incorporating novel highly loaded antimicrobial drug-silica coassembled particles (DSPs).MethodsDSPs were synthesized through coassembly of silica and octenidine dihydrochloride (OCT) antimicrobial surfactant. DSPs were loaded (1% and 2% wt) into epoxy resin sealer (AH Plus [AH]; Dentsply DeTrey GmbH, Konstanz, Germany) or calcium silicate–based sealer (EndoSequence Bioceramic Sealer (BC); Brasseler, Savannah, GA). OCT release from DSP-modified sealers was determined using liquid chromatography. Antimicrobial activity of sealers against planktonic or biofilm form Enterococcus faecalis was assessed using direct contact and membrane restricted tests. Sealer flow was tested according to ISO6876:2012.ResultsOCT release from BC + 1% or 2% DSPs was above the minimum inhibitory concentration following 2 days throughout the 30-day experiment, whereas OCT release from AH + 1% or 2% DSP was significantly below the minimum inhibitory concentration against E. faecalis (4 μg/mL) over the whole 30-day experimental period. All materials (with or without DSPs) killed planktonic bacteria initially. AH ± 1% or 2% DSPs had no antimicrobial activity after 7 days. BC + 1% or 2% DSPs maintained antibacterial activity over the 30-day period. Both modified and unmodified sealers completely inhibited the growth of E. faecalis biofilms after 24 hours of contact. DSPs decreased the flow of AH and BC sealers; for AH, the reduction was proportional to the amount of DSPs added. All modified and unmodified sealers, except for AH + 2% DSPs, were within the acceptable limits of ISO 6876 flow tests.ConclusionsDSPs enhanced the antimicrobial performance of BC but not AH, whereas the material’s flow remained compliant with ISO 6876 standards. Depending on the sealer, DSPs may enhance antimicrobial efficacy in root canal treatment and potentially improve treatment outcome.     

Antibacterial Activity of Endodontic Sealers by Modified Direct Contact Test Against Enterococcus faecalis

IntroductionThe antibacterial effectiveness of 7 different endodontic sealers, AH Plus, Apexit Plus, iRoot SP, Tubli Seal, Sealapex, Epiphany SE, and EndoRez against Enterococcus faecalis was studied in vitro.MethodsA modified direct contact test was used. Bacteria in suspension were exposed to the materials for 2–60 minutes by using sealers that were freshly mixed or set for 1, 3, and 7 days. The pH values and contact angles of sterile water on sealers at different times after setting were also measured.ResultsFresh iRoot SP killed all bacteria in 2 minutes, AH Plus in 5 minutes, EndoRez in 20 minutes, and Sealapex and Epiphany in 60 minutes. Freshly mixed Apexit Plus and Tubli Seal failed to kill all bacteria at 60 minutes. For 1-day and 3-day samples, iRoot SP and EndoRez had the strongest antibacterial activity, followed by Sealapex and Epiphany; Tubli Seal and AH Plus did n'ot show any significant antibacterial activity. Of all the samples, Apexit Plus had the lowest antimicrobial activity. The pH of the sealers could not alone explain their antibacterial effect.ConclusionsFresh iRoot SP, AH Plus, and EndoRez killed E. faecalis effectively. IRoot SP and EndoRez continued to be effective for 3 and 7 days after mixing. Sealapex and EndoRez were the only ones with antimicrobial activity even at 7 days after mixing.     

Wettability of root canal sealers on intraradicular dentine treated with different irrigating solutions

Objectives

The aim of this in vitro study was to evaluate the wettability of AH Plus and ThermaSeal Plus sealers on intraradicular dentine treated with different irrigating solutions.

Methods

Fifty anterior teeth were decoronated and split longitudinally. Each root half was divided into 5 groups (n = 10). Group I: 5 mL of 2.5% NaOCl + QMix. Group II: 5 mL of 2.5% NaOCl + 17% EDTA. Group III: 5 mL of 2.5% NaOCl + 7% maleic acid. Group IV: 5 mL of 2.5% NaOCl. Group V: 5 mL of distilled water. Irrigation regimens were performed for 1 min. Each specimen was placed inside a Dynamic Contact Angle Analyser. A controlled-volume droplet of sealer was placed on each specimen and the static contact angle was analysed.

Results

The contact angle made by both sealers with EDTA-irrigated dentine was significantly larger when compared to the other irrigants (P < 0.05). For ThermaSeal Plus, contact angles produced on maleic acid-, NaOCl- and distilled water-irrigated dentine were not significantly different, but were all significantly larger than the contact angle produced on QMix-irrigated dentine (P < 0.05). For AH Plus, contact angles produced on NaOCl- and distilled water-irrigated dentine were not significantly different, but were significantly larger than those made by maleic acid and QMix.

Conclusion

When used as a final irrigant, QMix favours the wetting of root canal dentine by both AH Plus and ThermaSeal Plus sealers. Maleic acid shows a promising result when compared to EDTA and NaOCl. Wettability of both sealers is the worst on EDTA-irrigated dentine.

Clinical significance

The present study highlights the effect of newer endodontic irrigating solutions on the wettability of sealers on to the root canal dentine, which is required for obtaining good obturation seal.     

The Antimicrobial Effect of Bioceramic Sealer on an 8-week Matured Enterococcus faecalis Biofilm Attached to Root Canal Dentinal Surface

IntroductionThe aim of this study was to test the antibacterial activity of bioceramic sealer in comparison with AH Plus (Dentsply International Inc, York, PA) on 8-week-old Enterococcus faecalis biofilms attached to root canal surfaces using a dentin infection model.MethodsThe canal surfaces of single-rooted intact extracted teeth were infected by growing E. faecalis biofilms for 8 weeks. AH Plus sealer and EndoSequence BC Sealer (Brasseler USA, Savannah, GA) were placed on the root canal wall of the dentin specimens for 24 hours and 2 weeks in humid conditions at 37°C. Infected samples incubated with no sealers for similar periods were used as the negative controls. Specimens were labeled with fluorescent viability staining, and confocal laser scanning microscopy was used as an assessment tool of the proportions of dead and live bacteria on canal walls after exposure to root canal sealers for the determined times.ResultsEndoSequence BC Sealer killed significantly more E. faecalis in biofilm attached to the canal surfaces when compared with AH plus sealer and control at both time points (P < .05–.0005).ConclusionsEndoSequence BC Sealer exhibited significant antimicrobial capacity in the presence of dentin for up to 2 weeks on an 8-week-old E. faecalis biofilm in comparison with AH Plus sealer.     

Comparative assessment of apical sealing ability of three different endodontic sealers: A scanning electron microscopic study

AimThe present in vitro SEM study compared the apical sealing ability of three different endodontic sealers used in single cone obturation technique.Material and method45 freshly extracted mandibular premolars with single canal and fully formed apices were selected. The samples were decoronated at/below the cementoenamel junction (CEJ) obtaining root lengths of 15 mm. The samples were instrumented using ProTaper rotary file system SX-F2. Following instrumentation the samples were randomly divided in three different groups for three different sealers to be used in single cone obturation technique. Group 1 EndoSequence BC, Group 2 GuttaFlow 2 and Group 3 AH Plus. The sealers were allowed to set completely. Following this the samples were longitudinally sectioned at the apical third and gold sputtered for SEM evaluation. The interphase between the radicular dentin and the root canal filling material were obtained in micrometers (μm) from the SEM images. Statistical analysis was performed.ResultsThe groups exhibited a statistically significant difference (p < 0.01). Group 3 presented with the highest interphase distance (p < 0.01), whereas Group 1 and 2 exhibited a statistically similar values (p > 0.05).ConclusionThe GuttaFlow 2 and Endosequence BC endodontic sealers showed better adaptation to the radicular dentin as compared to AH Plus sealer.     

USAGE OF CHLORHEXIDINE AS A FINAL IRRIGANT IN ONE-VISIT ROOT CANAL TREATMENT IN COMPARISON WITH CONVENTIONAL TWO-VISIT ROOT CANAL TREATMENT IN MANDIBULAR MOLARS: A RANDOMIZED CLINICAL TRIAL

ObjectivesThe effectiveness of 1-visit root canal treatment (RCT), especially for teeth with large periapical lesions, are still being debated. Although, the use of chlorhexidine (CHX) as a final irrigant have been recommended to provide an optimized approach in 1-visit RCT, there is limited knowledge about the outcome of 1-visit RCT using CHX as the final irrigant.AimThe aim of this randomized clinical trial was to evaluate the healing of mandibular molar teeth with large periapical lesions after RCT that was completed in 1 visit using 2% CHX as a final irrigant, comparing the results with a conventional 2-visit RCT as a control group.MethodologyThis study is a prospective, parallel-designed, and single-blinded randomized clinical trial. One-hundred asymptomatic mandibular molar teeth with large periapical lesions were randomly assigned to 2 groups. All teeth were instrumented with Reciproc files with 2.5% sodium hypochloride (NaOCl) and 5% ethylenediaminetetraacetic acid (EDTA) as irrigants. In the intervention group, half of the teeth were treated in 1 visit, receiving an additional final rinse with 2% CHX before obturation; the other half of the teeth, however, were treated in 2 visits with calcium hydroxide (CH) dressings, in the control group. All root canals were obturated with Reciproc gutta-percha cones and AH Plus root canal sealer. All patients were recalled and investigated clinically and radiographically for 48 months. Periapical healing was evaluated statistically using the Mann-Whitney U test, followed by the Friedman and the Wilcoxon tests (α = 0.05).ResultsDuring the 48-month follow-up process, 86 teeth (44 in 1-visit and 42 in 2-visit group) were examined. There were no significant differences between the 2 groups regarding the radiographic healing rates (1-visit group 91% and 2-visit group 88%) (P > .05).ConclusionIn this study, 1-visit RCT using 2% CHX as final irrigant in asymptomatic mandibular molars with large periapical lesions produced favorable healing results, similar to 2-visit root canal treatment with calcium hydroxide.     

Influence of the final irrigation solution on the push-out bond strength of calcium silicate-based,epoxy resin-based and silicone-based endodontic sealers

Odontology - The aim was to evaluate the influence of different irrigation solutions on the push-out bond strength (POBS) of three different sealers (AH Plus, BioRoot RCS, GuttaFlow2). Root canals...     

Dentin Extends the Antibacterial Effect of Endodontic Sealers against Enterococcus faecalis Biofilms

Introduction

The purpose of this study was to evaluate the antimicrobial effects of root canal sealers on Enterococcus faecalis biofilms in dentinal tubules by using a novel dentin infection model.

Methods

Cells of E. faecalis were introduced into the dentinal tubules by centrifugation and incubated in brain-heart infusion broth for 3 weeks. An equal thickness of AH Plus, Endosequence BC sealer (BC sealer), and pulp canal sealer EWT (PCEWT) was placed on the root canal wall of the dentin specimens for 1, 7, and 30 days in humid conditions at 37°C. Gutta-percha and water were used in a similar manner as the tested sealers. The proportions of dead and live bacteria inside the dentinal tubules after exposure to root canal sealers were assessed by confocal laser scanning microscopy.

Results

Significantly more bacteria were killed in the 3 sealer groups than in the 2 control groups (P < .05). BC sealer and AH Plus resulted in significantly more dead cells than PCEWT did. There was no statistically significant difference between BC sealer and AH Plus at any time point (P > .05). Thirty days of exposure to BC sealer and AH Plus resulted in significantly more dead bacteria in dentin than 7-day and 1-day exposures in the biofilms, whereas no statistically significant increase of the proportion of dead bacteria was detected between 7-day and 30-day PCEWT (P > .05).

Conclusions

The 3 endodontic root canal sealers had antibacterial effects against E. faecalis in the dentinal tubules. BC sealer and AH Plus had superior antibacterial effects compared with PCEWT. The antibacterial effects of sealers in dentinal tubules continued after setting.     

终末冲洗方案对根管封闭剂与根管壁牙本质粘接强度的影响

目的：比较不同终末冲洗方案对根管封闭剂 AH Plus 及 GuttaFlow 与根管壁牙本质之间粘接强度的影响。方法：60颗单根离体人牙截冠后用冠向下法进行常规根管机械化学预备,按终末冲洗方案随机分为3组（n ＝20）。组1：17％乙二胺四乙酸（EDTA）＋2％氯己定（CHX）;组2：5．25％次氯酸钠（NaOCl）＋17％ EDTA;组3：0．9％生理盐水（NS）对照组。每组根据使用的根管封闭剂分为2个亚组（n ＝10）：组 a．AH Plus;组 b．GuttaFlow。每个牙根自冠方向根方获取3个厚度约为2mm 的水平切片进行薄片推出实验。体视显微镜下观察断裂形式。结果：3种冲洗方案,AH Plus 的粘接强度均显著高于GuttaFlow（P ＜0．05）。使用 AH Plus 根管充填时,组1、组2和组3的粘接强度分别为（5．37±2．80）MPa、（8．81±4．38） MPa、（9．07±2．77）MPa（组1与组2或组3比较,P ＜0．05,组2与组3间比较,P ＞0．05）。使用 GuttaFlow 根管充填时,组1、组2和组3粘接强度分别为（1．40±0．59）MPa、（1．26±0．62）MPa 和（1．05±0．27）MPa（两两比较,P ＞0．05）。各组试件均以混合型断裂为主要断裂方式,但 GuttaFlow 组内粘接型断裂形式所占比例显著高于 AH Plus 组。结论：GuttaFlow 对牙本质的粘接强度显著低于 AH Plus。17％ EDTA ／2％ CHX 终末冲洗方案可显著降低 AH Plus 与根管壁牙本质的粘接强度,但对 GuttaFlow 的粘接性能无显著影响。     

Effect of three different photosensitizers in photodynamic therapy on bond strength of a calcium silicate-based sealer to radicular dentin

To evaluate the effect of the photodynamic therapy (PDT) using with different photosensitizers on the bond strength of BioRoot RCS (BR) to radicular dentin by comparing with AH Plus (AH). The shaped root canals of 80 human mandibular premolars were divided into four groups based on the final disinfection protocol: NaOCl/EDTA, PDT with methylene Blue (MB), PDT with curcumin (CUR) and PDT with toluidine blue O (TBO) (n = 20). Each group was randomly divided into two subgroups (n = 10), according to the endodontic sealer used for obturation (n = 10). The test of push-out bond strength (PBS) was performed using an universal test machine. The data were analysed using ANOVA, Tukey post-hoc, and independent sample t-test (α = 0.05). MB-BR group showed the highest PBS at the cervical level (p < 0.05). The selection of the photosensitizer in PDT influenced adhesion of root canal sealers to radicular dentin.     

Influence of endodontic irrigants on resin sealer bond strength to radicular dentin

The present study evaluated the influence of 2% chlorhexidine and 2.5% sodium hypochlorite on the resin sealer/dentin interface bond strength of AH Plus/gutta-percha and Epiphany/Resilon. Seventy-two extracted bovine incisors were randomly distributed into 6 groups according to irrigant and sealers: G(S+AH)=physiologic saline solution+AH Plus/gutta-percha; G(S+Ep)=physiologic saline solution+Epiphany/Resilon; G(H+AH)=2.5% sodium hypochlorite (NaOCl)+AH Plus/gutta-percha; G(H+Ep)=2.5% NaOCl+Epiphany/Resilon; G(C+AH)=2% chlorhexidine (CHX)+AH Plus/gutta-percha; and G(C+Ep)=2% CHX+Epiphany/Resilon. After 7 days at 37°C and 100% humidity, the roots were cut transversally on the long axis of the tooth in 0.8 mm (±0.09)-thick slices; these slices were then subjected to the push-out test. Data were analyzed using a 2-way ANOVA and Tukey tests at 5% significance. The AH Plus/gutta-percha groups showed significantly higher bond strength than the Epiphany/Resilon groups, regardless of the irrigant used (p<0.001). Sodium hypochlorite adversely affected bond strength in the AH Plus group, whereas chlorhexidine did not influence the push-out bond strength of either sealer (p<0.05). Two percent chlorhexidine did not adversely affect the bond strength of the sealers, whereas 2.5% sodium hypochlorite solution damaged AH Plus/gutta-percha bond strength.     

A Novel Polyurethane Expandable Root Canal Sealer

IntroductionEndodontic sealers play a vital role in the obturation of root canal space. The aim of this study was to evaluate the utility of a recently developed polyurethane expandable sealer (PES), along with its cytotoxicity and dimensional changes.MethodsL929 fibroblasts and an cell viability assay (MTS assay) were used to determine the cytotoxicity of dental sealers (AH Plus [Dentsply Maillefer, Ballaigues, Switzerland], Sure-Seal Root [Sure Dent Corporation, Gyeonggi-do, South Korea], and the PES) at 24, 48, 72, and 96 hours. An advanced choroidal neovascularization model was used to assess the effect of these sealers on angiogenesis. Thirty-six extracted single-rooted human teeth were prepared and randomly divided into 3 groups (n = 12). Obturation was performed with gutta-percha and a sealer using lateral compaction as follows: group 1, AH Plus; group 2, Sure-Seal; and group 3, PES. The average depth of sealer penetration into dentinal tubules was measured with a scanning electron microscope. Data were analyzed using 1-way analysis of variance and post hoc Tukey tests (level of significance, P < .05).ResultsThe values of MTS, choroidal neovascularization, and the penetration depth of PES were significantly higher than in other experimental groups (P < .05). The lowest values were noted in specimens of AH Plus, whereas the highest were detected in the PES group.ConclusionsPES showed promising results in terms of biocompatibility and dentinal tubule adaptation and penetration.     

A microleakage study of gutta-percha/AH Plus and Resilon/Real self-etch systems after different irrigation protocols

The development and maintenance of the sealing of the root canal system is the key to the success of root canal treatment. The resin-based adhesive material has the potential to reduce the microleakage of the root canal because of its adhesive properties and penetration into dentinal walls. Moreover, the irrigation protocols may have an influence on the adhesiveness of resin-based sealers to root dentin.

Objective

The objective of the present study was to evaluate the effect of different irrigant protocols on coronal bacterial microleakage of gutta-percha/AH Plus and Resilon/Real Seal Self-etch systems.

Material and Methods

One hundred ninety pre-molars were used. The teeth were divided into 18 experimental groups according to the irrigation protocols and filling materials used. The protocols used were: distilled water; sodium hypochlorite (NaOCl)+eDTA; NaOCl+H₃PO₄; NaOCl+eDTA+chlorhexidine (CHX); NaOCl+H₃PO₄+CHX; CHX+eDTA; CHX+ H₃PO₄; CHX+eDTA+CHX and CHX+H₃PO₄+CHX. Gutta-percha/AH Plus or Resilon/Real Seal Se were used as root-filling materials. The coronal microleakage was evaluated for 90 days against Enterococcus faecalis. Data were statistically analyzed using Kaplan-Meier survival test, Kruskal-Wallis and Mann-Whitney tests.

Results

No significant difference was verified in the groups using chlorhexidine or sodium hypochlorite during the chemo-mechanical preparation followed by eDTA or phosphoric acid for smear layer removal. The same results were found for filling materials. However, the statistical analyses revealed that a final flush with 2% chlorhexidine reduced significantly the coronal microleakage.

Conclusion

A final flush with 2% chlorhexidine after smear layer removal reduces coronal microleakage of teeth filled with gutta-percha/AH Plus or Resilon/Real Seal SE.