Zinc Oxide Eugenol-based Sealer Research Articles

Bacterial Leakage Evaluation of Three Root Canal Sealers with Two Obturation Techniques: An in Vitro Study

Background: The purpose of this study was to compare the quality of the coronal seal of three root canal sealers and two obturation techniques using the bacterial penetration method. Methods and Results: A total of 132 single-rooted human teeth with fully developed apices were used. The teeth were randomly assigned to three experimental groups according to the endodontic sealer used. Group 1: Samples (n=44) were obturated using a zinc oxide eugenol-based sealer, Pulp Canal Sealer EWT. Group 2: Samples (n=44) were obturated using an epoxy resin-based sealer, AH Plus. Group 3: Samples (n=44) were obturated using a bioceramic-based root canal sealer, Well-Root ST. Each group was subdivided into 2 equal subgroups in accordance with the obturation technique being used: CLCT and ThOT. Thus, 6 subgroups were formed: Sub-1A: Pulp Canal Sealer/CLCT; Sub-2A: AH Plus/CLCT; Sub-3A: Well-ROOT ST/CLCT; Sub-1B: Pulp Canal Sealer/ThOT; Sub-2B: Ah Plus/ThOT; Sub-3B: Well-ROOT ST/ThOT. A dual-chamber device was used to evaluate bacterial leakage. Fresh medium and E. faecalis were added to the upper chamber every 4 days. The broth was monitored for color change daily for 33 days. Significant differences were found among Sub-2A vs. Sub-1B (P=0.023), Sub-1A vs. Sub-3A (P=0.014), Sub-1A vs. Sub-2B (P=0.024), Sub-1A vs. Sub-3B (P=0.002), Sub-3A vs. Sub-1B (P=0.003), Sub-2B vs. Sub-1B (P=0.005), and Sub-1B vs. Sub-3B (P<0.0001). There was no significant difference in the average occurrence of turbidity between CLCT and ThOT (P=0.718) Conclusion: Regardless of the obturation technique, all root canal sealers exhibited leakage; however, the bioceramic-based root canal sealer appeared to perform better than the epoxy resin-based sealer and the zinc oxide eugenol-based sealer.

Comparison of apical sealing ability between bioceramic and zinc oxide eugenol-based sealer during root canal treatment, in vitro

Obturation with a sealer material that provides an adequate apical sealing ability is required to prevent endodontic treatment failure due to microleakage. However, there are no sealers that meet all the physical and chemical properties to be able to hermetically seal the root canal system to date. Various sealer materials have been developed in recent years including the use of bioceramic materials which are claimed to have excellent biocompatibility to tissues. This study aimed to compare the apical sealing ability of bioceramic-based and zinc oxide eugenol (ZOE)-based sealer in root canal treatment. A total of 27 extracted mandibular premolars were decoronated to the standard root length of 14 mm. The root canals were prepared with a crown-down technique using manual instrument to file F3 (30/.09). The samples were then divided into three groups: obturation with bioceramic-based sealer (n=9); ZOE-based sealer (n=9); and control group (n=9). Microleakage was measured using a dye penetration method with 1% methylene blue and observed under stereomicroscope at x20 magnification. The mean of the maximum penetration length from the lowest to the highest was found in the bioceramic-based sealer group (0.825 mm), the ZOE-based sealer group (3.850 mm), and the control group (4.444 mm). One-way ANOVA test showed a significant difference in the maximum penetration length between the three groups (p<0.05). The post hoc LSD test showed a significant difference in the maximum penetration length between the bioceramic-based and ZOE-based sealer groups (p<0.001). Obturation with bioceramic-based sealer provides a better apical sealing ability than that with ZOE-based sealer.

Fracture Resistance of Roots Obturated with Resilon and EndoREZ with Self-Adhesive Root Canal Sealers

<sec> <title>Objective:</title> This laboratory study aimed to evaluate the effect of self-adhesive root canal sealers on the fracture strength of root canals filled with Resilon or EndoREZ. </sec> <sec> <title>Materials and Methods:</title> A total of eighty extracted mandibular premolar teeth were selected in this in-vitro study. All teeth were instrumented using a crown-down technique by FlexMaster rotary NiTi files. Specimens were divided into 4 test groups (n = 20) according to the sealer material: RS; RealSeal, RSS; RealSeal SE, MS; MetaSeal, and CG; (control group) zinc oxide eugenol-based sealer. Each main group was distributed into two subgroups (n = 10) according to the filling material either Resilon or EndoREZ and gutta-percha (n = 20) in the control group. Each root was mounted in acrylic resin blocks and subjected to fracture in a universal testing machine. The load values at root specimens fractured were registered in Newton’s and the data were analyzed using two-way analysis of variance and the Tukey HSD test (α = 0.05). </sec> <sec> <title>Results:</title> The two-way analysis of variance analysis indicated that the filling material had a significant effect on the fracture strength of endodontically treated teeth (p < 0.05) but not the sealer materials (p≥.05). Higher mean fracture strength was recorded in MetaSeal and Resilon group (1281.90±200.34 N) and lower mean fracture strength was shown in RealSeal and EndoREZ group (847.55±191.04 N). </sec> <sec> <title>Conclusion:</title> Self-adhesive (fourth-generation) resin sealers increased the fracture strength of root teeth more than self-etching (third-generation) root canal sealers when used with EndoREZ points. </sec>

Effects of dentine surface cleaning on bonding of a self-etch adhesive to root canal sealer-contaminated dentine

ObjectivesTo compare the effectiveness of different sealer cleaning methods on bonding of a self-etch adhesive to root canal sealer-contaminated dentine. MethodsForty-nine extracted molars were divided into seven groups. Dentine surfaces were exposed and cotaminated with a thin layer of epoxy resin-based sealer (AH Plus (AHP)) or zinc oxide eugenol-based sealer (Pulp Canal Sealer (PCS)). Three cleaning protocols were examined: dry cotton pellet, 70% ethanol-saturated cotton pellet or a surfactant-based cleaner (KatanaTM Cleaner (KC), Kuraray Noritake Dental Inc.). Uncontaminated dentine served as control. The dentine surfaces were bonded with a two-step self-etch adhesive and restored with resin composite. Bond strength testing was performed using a microtensile approach. Two teeth from each group were used for scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). The pulpal floor of the teeth was covered with sealer and cleaned. The percentage of zinc/zirconium on the dentine surface was detected to indicate the amount of remnant sealer. ResultsTensile bond strength for uncontaminated dentine control was 46.4±7.3 MPa; bond strength decreased significantly for the dry cotton group (29.6±4.2 MPa for AHP, 24.7±4.7 MPa for PCS, p<0.05). Both ethanol and KC restored bonding performance after cleaning, with no significant difference from the control. Significantly lower MTBS was observed for the ZOE/ethanol subgroup (38.9±5.1 MPa). Cleaner surfaces and less zinc/zirconium elements were identified by SEM/EDX after cleaning with ethanol or KC. ConclusionsKatanaTM Cleaner decontaminates root canal sealer-smeared dentine surfaces effectively and restores the bonding performance of a self-etch adhesive to dentine. Clinical significanceThe surfactant-based KatanaTM Cleaner, originally designed for cleaning zirconia surfaces prior to adhesive bonding, may be used as for cleaning dentine that has been contaminated with unset root canal sealers after root canal treatment to restore the bonding strength of a self-etch adhesive to sealer-contaminated dentine.

PERBEDAAN EFEKTIVITAS PELARUT ORANGE OIL TERHADAP SEALER BERBASIS RESIS DAN ZINC OXIDE EUGENOL

This study aims to determine the differences in the effectiveness of orange oil solvent against resin-based sealers and zinc oxide eugenol. The samples of this study were resin based sealers and zinc oxide eugenol based sealers which were molded in a cylindrical mold made of aluminum with a diameter of 10 mm and a height of 3 mm. The total sample size in this study was 60 samples, then divided into 4 groups, 2 groups for resin-based sealers with a time of 2 minutes and 5 minutes, and a sealer based on zinc oxide eugenol with a time of 2 minutes and a time of 5 minutes, after which it was put into incubator with a temperature of 370C for 48 hours, then weighed for each group. Data analysis used paired T test with the Kolmogorov Smirnov normality test. The results showed that the orange oil solvent did not have a significant difference to the resin-based sealers and the zinc oxide eugenol-based sealers. At the immersion time of 2 minutes, the solubility of resin-based sealers and zinc oxide eugenol did not have significant differences (p&gt; 0.05). Based on the research results, it can be concluded that orange oil solvent is equally effective in both sealers, neither is more effective than the other&#x0D; Keywords: Orange Oil solvent, resin sealer, Zinc Oxide Eugenol sealer.&#x0D;

A Cross-Sectional Study on the Preference of Root Canal Sealers Among Pediatric Dentists For Obturating Permanent Teeth

Utilisation of root canal sealers to perform obturation procedures is an endorsed method in endodontics and has an indispensable role in the success of treatment. The objective of this study was to explore the pediatric dentists’ preference for root canal sealers for obturating permanent teeth. 360 permanent teeth with gutta-percha obturation done by pediatric dentists were analyzed for the study. The variety of root canal sealers that are utilised for obturating the permanent teeth by pediatric dentists were assessed. The data were obtained from a patient management software. Chi-square test was performed. Out of the 360 permanent teeth, 186 teeth were obturated using resin-based sealers, 101 teeth using zinc oxide eugenol-based sealers and 73 teeth were obturated using calcium hydroxide-based sealers, with statistically significant difference between the three materials (P&lt;0.05). Based on the findings of the present study, resin sealers followed by zinc oxide eugenol sealers and calcium hydroxide sealers were more preferred by pediatric dentists for root canal therapy in permanent teeth.

The effect of smear layer on bacterial penetration through roots obturated using zinc oxide eugenol-based sealer

BackgroundSmear layer removal has been shown to reduce bacterial penetration through root canal obturations when resin-based endodontic sealer is used. The purpose of this in vitro study was to test this effect when a non-resin-based sealer is used.Material and methodsThirty root segments were assigned to the following groups: Smear layer removed (n = 8); smear layer retained (n = 8); negative controls (n = 10; 5 with smear layer, 5 without); and positive controls (n = 4; 2 with smear layer, 2 without). After rotary instrumentation, smear layers were removed in the treatment group and half of controls using 17% ethylenediamenetetraacetic acid (EDTA) prior to obturation. Each obturated root was affixed into a dual-chamber leakage model employing Streptococcus mutans. Roots were incubated at 37 °C for 120 d. Days until lower chamber turbidity occurred was recorded for each sample, and data were analyzed using Kaplan-Meier survival curve analysis (p = 0.05).ResultsNo negative controls leaked, while all positive controls were turbid within 1 day. Mean days to leakage for roots with smear layer intact was 82.75 (+/− 33.29, 95% CI), although three never leaked. Mean days to leakage through roots with smear layer removed was 46.25 (+/− 26.67, 95% CI), and all leaked. Treatment survival curves were significantly different (p = 0.048).ConclusionsUnder the conditions and limitations of this study, retaining the smear layer reduced the rate of bacterial penetration through canals which had been obturated using zinc oxide eugenol (ZOE) -based sealer.

Current Trends in Practice of Residents in the Saudi Board of Endodontics Program.

Objectives The purpose of the current study was to collect information about some techniques and armamentarium currently used by the Saudi Board of Endodontics residents in relation to the technical steps of root canal therapy. Materials and Methods A web-based survey was sent to the Saudi Board of Endodontics residents, based in the western area of Saudi Arabia. The survey assessed controversial concepts, and collected information regarding new instruments and materials, used in the technical steps of nonsurgical root canal treatment. A one-sample chi-square test, with a 95% level of significance, was applied to determine whether there were significant differences between respondents’ answers. Results A total of 45 out of 50 residents (90%) responded to the questionnaire. The majority of Saudi Board residents of Endodontics, who participated in this survey, used the mean of working length (ML) measured by periapical X-Ray and apex locator in the presence of a radiographic lesion (63.3%), and maintained apical patency in all cases (80.0%). ProTaper Universal (40%) and ProTaper Next (41.2%) were the most common NiTi rotary systems used for root canal instrumentation. Thirty percent of respondents used adjunct device with irrigation, and 80% advocated smear layer removal. Zinc oxide–eugenol-based sealers were the most common used sealers (70%), and most residents (86.6%) did not advocate sealer extrusion. Conclusions This study revealed that residents of the Saudi Board of Endodontics program adopt new endodontic technologies. There is, however, a need for more investigations regarding this objective, including responses from all residents in Saudi Arabia.

Effect of Adding Antibiotic to Zinc Oxide Eugenol-Based Sealer upon the Apical Seal (In vitro study)

Effect of Adding Antibiotic to Zinc Oxide Eugenol-Based Sealer upon the Apical Seal (In vitro study)

Effect of Time of Interradilarcular Preparation on Apical Microleakage of Endodontically Treated Teeth

Purpose: This study was conducted to evaluate apical leakage of post space preparation when performed at different time intervals immediately after root canal obturation (after setting of the sealer used) or delayed after two weeks. Materials and methods: Forty-five extracted human anterior single rooted teeth were selected and placed in sterile physiologic saline solutions. Teeth were decoronated perpendicular to their long axis and 2mm above the cemento-enamel junction (CEJ). The canals were filed to mater apical file size #40 using step-back tech. The root canals were enlarged and flared to size #55. The specimens were divided randomly into 3 equal groups(15 samples each) , according to type of sealer that used during root canal treatment group (1) Eugenol-based sealer, group(2) Calcium hydroxide-based sealer and group (3) Resin –based sealer, After root canal obturation, the specimens were further subdivided into three subgroups (5 samples each): subgroup (A) without post space preparation as control, Subgroup (B) with immediate post space preparation and Subgroup (C) with delayed post space preparation. Results: Calcium hydroxide based sealer group recorded the highest mean value of apical leakage followed by Zinc oxide eugenol-based sealer and AD SEAL resin based sealer which recorded the lowest mean value with no statistical significant difference (P˃0.05). Regarding the effect of time interval control sub group recorded the statistically significant lowest mean value followed by immediate subgroup, while delayed subgroup recorded the statistically significant highest mean value (P ˂0.05). Conclusions: The type of sealer had major effect on the apical seal of endodontically treated teeth. Post-space preparation affects the apical seal of endodontically treated teeth. The effect of immediate preparation on apical seal was significantly lesser than delayed post space preparation.

Effect of root canal sealers on the fracture resistance of endodontically treated teeth: a systematic review of in vitro studies.

The purpose of this study was to systematically review and critically analyze the published data of in vitro studies testing the effect of root canal sealers on the fracture resistance of endodontically treated teeth. A comprehensive literature search was performed by using the Medline, Scopus, Web of Science, Cochrane, and Open Grey databases. A hand search of the reference lists of identified articles was also performed. Two reviewers critically assessed the studies for eligibility against inclusion and exclusion criteria and performed data extraction. Evaluation of the risk of bias of the studies was performed. A total of 48 studies were assessed for eligibility. Of these, 20 met the inclusion criteria and were included in the systematic review. All studies had a medium or high risk of bias. Although the majority of the studies reported that the use of root canal sealers increased the fracture resistance of endodontically treated teeth, conflicting evidence was found for the reinforcing effect of resin, glass ionomer, and calcium silicate-based sealers while there was moderate evidence for zinc oxide eugenol-based sealers in favor of no reinforcing effect. On the basis of available evidence, the use of root canal sealer increases the fracture resistance of endodontically treated teeth. However, included studies presented considerable risk of bias. Regarding the comparisons among the sealers, no conclusions could be drawn for the superiority of one sealer type to another. A considerable heterogeneity was found in the methodologies of included studies. Therefore, this review strongly suggests the development of standardized methods to test the reinforcement effect of root canal filling materials in in vitro studies.

Comparative Evaluation of Cytotoxicity of Root Canal Sealers on Cultured Human Periodontal Fibroblasts:In vitroStudy

To evaluate and compare the cytotoxic effects of different types of root canal. The sealers were eluted with culture medium for 1 hour, 7 days, and 14 days. Cell viability was estimated by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and trypan blue exclusion method on human periodontal ligament (PDL) fibroblast cells. Sealers used are mineral trioxide aggregate (MTA)-based sealer (MTA Fillapex, Angelus), calcium hydroxide-based sealer (Apexit Plus, Ivoclar Vivadent), resin-based sealer (AH Plus, Dentsply), and zinc oxide eugenol-based sealer (Tubli Seal, SybronEndo). The order of cytotoxicity through MTT assay, at the end of the second week, was observed as MTA Fillapex> Tubli Seal> Apexit Plus > AH Plus. The percentage cell viability obtained after trypan blue exclusion method decreased in the order of Apexit Plus> Tubli Seal> AH Plus> MTA Fillapex, which was similar to the reported cytotoxicity from the MTT assay after 1 hour. Each type of sealer showed moderate-to-severe cytotoxic response when compared with the control. The MTA Fillapex was found to be the most cytotoxic sealer. Use of resin-based material as a root canal sealer may result in a more favorable response to PDL fibroblasts. Having knowledge of the cytotoxicity of various sealers will help in increasing patient's comfort.

혼합 직후 또는 경화된 근관용 실러의 한천중층시험

This study was performed to evaluate the cytotoxicity of root canal sealers before and after setting procedures by an agar overlay test. Six kinds of root canal sealers were used in this experiment: AH Plus, AH 26, ADSEAL, DIA-PROSEAL, Tubli-Seal, and Sealapex. Test materials were prepared as either freshly mixed type of provided components or hardened specimens after setting procedures in each Teflon ring-shaped holder. Agar overlay test was done with L929 mouse fibroblast cells and positive, negative and test materials were set on the solidified agar medium. After 24 hrs, decolorization index and lysis index were evaluated and its cell response was interpretated. Decolorization zones and lysis values by all root canal sealers used in this study showed index 5 when freshly mixed root canal sealers were placed. Decolorization zones by AH Plus and AH 26 were larger than those by other two kinds of resin sealers after setting procedures. Zinc oxide eugenol-based sealer, Tubli-Seal, showed decolorization index 3 and lysis index 5, otherwise, calcium hydroxide based-sealer, Sealapex, did decolorization index 2 and lysis index 4 after hardening procedures. Among test materials, DIA-PROSEAL had the least cytotoxicity after hardening, followed by ADSEAL and Tubli-Seal. In conclusion, all root canal sealers had the severe cytotoxic effects when freshly mixed materials were tested. However, cytotoxicity was reduced after sealer hardening, especially in case of DIA-PROSEAL.

Evaluating the attitudes of general dental practitioners in Gaziantep about endodontics

The purpose of this study is to determine the level of knowledge of dentists working in Gaziantep about the stages of root canal treatment. Questionnaires were reached to 118 general dental practitioners working in Gaziantep. Questionnaire was including questions such as age, gender, year of graduation, root canal medicament, root canal sealer, irrigation solution, use of rotary instrument and apex locator, number of sessions, indication of retreatment. Results were analyzed with chi-square test. A hundred of the dentists accepted to be included in the survey. The most frequently preferential inter-appointment medicament was calcium hydroxide with a ratio of 84 % (p < 0,05). Resin based sealers are the mostly used sealers (p < 0,05) while endomethazone and zinc oxide eugenol based sealers (ZOE) are used less frequently. Composite is preferred by 71 % of respondents for coronal restoration (p < 0,05) while amalgam is the second most used material with the ratio of 41 %. Single visit treatment is carried out especially by 15-20 and 0-5 years graduate to single-double rooted teeth. For working length determination, 64 % of respondents prefer radiographic method, 32 % of them use apex locators while 42 % rely upon tactile sensation. Among the respondents, 41% use only hand files for preparation while % 59 use rotary instruments. Sodium hypochlorite is the most used irrigant while chlorhexidine is used less. General dental practitioners in Gaziantep should obviate the information deficiencies about different steps of endodontics.

Antibacterial efficacy of three root canal sealers against Enterococcus faecalis and Candida albicans: An in vitro study

Aim: The aim of this in vitro study was to compare the antimicrobial efficacy of calcium hydroxide-based sealer (Apexit Plus), zinc oxide eugenol-based sealer (Endoflas FS) and resin-based sealer (EndoRez) root canal sealers against Enterococcus faecalis microbial type culture collection (MTCC) 439 and Candida albicans MTCC 239 using agar diffusion test. Materials and Methods: In the present study, 20 Mueller Hinton agar (MH agar) plates were employed. Three wells were made by removal of agar at equidistant points and filled with root canal sealers according to manufacturer's instructions. The strains of the bacteria and fungi used in this study were E. faecalis MTCC 439 and C. albicans MTCC 227. Both micro organisms were grown at 37°C for 24 h in MH Broth and seeded into MH agar to produce a turbidity of 0.5 on the McFarland scale, which corresponds to a concentration of 10 8 CFU/mL. This MH broth was used as a second layer. The seeded agar was then added over the plates immediately after the insertion of sealer cements. After incubation, the diameters of zones of inhibition around the plates were measured. Results: The results were statistically analyzed using two way ANOVA test. Against both the micro organisms used in this study, Endoflas FS showed the largest zones of inhibition followed by Apexit Plus and EndoRez. Conclusion: Within the limitations of this study, it can be concluded that: Root canal sealers showed different inhibitory effects depending on their types and microbial strains tested. Against Enterococcus faecalis and Candida albicans, zinc oxide based sealers showed the highest microbial zones of inhibition followed by the calcium hydroxide based sealer and resin based sealer respectively

Comparative evaluation of push-out bond strength of a MTA-based root canal sealer

Aim: To evaluate the bond strength to root dentin of three root canal sealers: a mineral trioxide aggregate (MTA)-based sealer (MTA Fillapex®), an epoxy resin-based sealer (AH Plus®), and a zinc oxide eugenol-based sealer (EndoFill®). Methods: Thirty extracted single-root human teeth of similar sizes and circular canals were prepared using #3 and #2 Gates Glidden drills in the cervical portion of the canal and K3® rotary instruments to a size #25/0.06 to working length. Irrigation with 0.5 mL 2% chlorhexidine gel was used before and 1 mL saline after each instrument. The smear layer was removed with 3 mL 17% EDTA for 3 min. The samples were sectioned horizontally into eight 1±0.1 mm-thick serial slices and then the push-out test was carried out. Two-way analysis of variance (ANOVA) and the post-hoc Tukey test were used for the analysis of the data with a significance level of 5%. Results: AH Plus presented significantly higher bond strengths (p<0.05) than the other sealers, while MTA Fillapex showed the lowest bond strengths (p<0.05). Conclusions: The present study concluded that EndoFill® sealer and MTA FillApex® core combination were not superior to AH Plus® sealer and gutta-percha core combination.

Effects of calcium phosphate endodontic sealers on the behavior of human periodontal ligament fibroblasts and MG63 osteoblast‐like cells

In regard to biological properties of endodontic sealers, there are many characteristics that should be considered. The aim of this study was to examine the biological effects of new calcium phosphate-based root canal sealers, CAPSEAL I and CAPSEAL II (CPS), on human periodontal fibroblast cells by examining the expression levels of inflammatory mediators and to compare the effects of CPS on the viability and osteogenic potential of human osteoblast MG63 cells compared to those of other commercially available calcium phosphate sealers [Apatite Root Sealer type I (ARS I) and Apatite Root Sealer III (ARS III); Sankin Kogyo, Tokyo, Japan] and a zinc oxide eugenol-based sealer (Pulp Canal Sealer EWT [PCS EWT]; Kerr, Detroit, MI). The levels of IL-6 in the new CPS group (CAPSEAL I, II) were higher than those in the control and all experimental groups at all time points after 2 h. TGF-β1 and FGF-1 levels decreased at 72 h compared to the levels in the control, in cells treated with every sealers except ARS I. The new CPS sealers showed low cytotoxicity. Reverse transcription polymerase chain reaction showed that CAPSEAL I, II, and Apatite Root Sealer type III induced expression of early stage markers of differentiation (alkaline phosphatase and osteopontin) at 7 days. Also, new CPS showed higher mineralized nodule formation at 28 days. These results suggest that CAPSEAL I and II facilitate the periapical dentoalveolar and alveolar healing by controlling cellular mediators from PDL cells and osteoblast differentiation of precursor cells.

An Assessment of Antibacterial Activity of Four Endodontic Sealers on Enterococcus faecalis by a Direct Contact Test: An In Vitro Study

Aim. To evaluate the antibacterial activity of four endodontic sealers on Enterococcus faecalis by a direct contact test. Material and Methods. Enterococcus faecalis was used as a test organism. Direct contact test which is based on measuring the effect of close contact between test bacteria and tested material on the kinetics of bacterial growth was performed to overcome the disadvantages of agar diffusion test. The sealers tested were zinc oxide eugenol-based sealer, glass-ionomer-based sealer, polydimethyl-siloxane-based sealer, and urethane dimethacrylate resin-based sealer. Data was collected by recording the optical density with the help of a spectrophotometer. Results. The sealers exhibited different inhibitory effects. The results obtained were subjected to statistical analysis by Kruskal Wallis analysis of variance and Dunn's multiple comparison test. Group comparison showed very highly significant difference between the groups. Conclusion. Zinc oxide eugenol-based sealer was the most effective and urethane dimethacrylate resin-based sealer was the least effective against Enterococcus faecalis, whereas glass-ionomer-based and polydimethyl-siloxane-based sealers were effective only for a short period. Inhibition of the bacterial growth is related to the direct contact of the microorganism with the sealer.

A scanning electron microscopic evaluation of the penetration of root canal dentinal tubules by four different endodontic sealers : A zinc oxide eugenol-based sealer, two resin-based sealers and a Polydimethylsiloxane - based sealer : An in vitro study

Aim and Objectives : The purpose of this study is to evaluate and compare the depth of penetration of Tubli- Seal[EWT], AH Plus, EndoREZ and GuttaFlow sealers into the root canal dentinal tubules using a scanning electron microscope. Materials and methods : Hundred extracted permanent human mandibular premolars with a single root canal were used for the purpose of this study. All teeth were prepared using ProTaper Nickel Titanium Rotary System to apical size #30. After removal of smear layer, teeth were randomly divided into five groups of 20 teeth each. Tubli-Seal [EWT], AH Plus, EndoREZ and GuttaFlow were used as sealers in Group I, Group II, Group III and Group IV respectively. In the control i.e. Group V, no sealer was used. All the teeth were obturated with the thermoplasticized gutta-percha technique using the E&Q Plus System. After storage at 370 C and 100% humidity for 14 days, the teeth were sectioned at 3, 5 and 7 mm from the root apex to obtain 2 mm thick specimens. The surfaces of the specimen representing the 3 and 5 mm level were observed using a scanning electron microscope (SEM). The maximum depth of sealer penetration into the dentinal tubules was measured for each section in microns. Statistical analysis was performed by using the Mann–Whitney test to compare the penetration of each sealer. Results and Conclusion : Within the parameters of the present study it was concluded that the dentinal tubule penetration of sealers is affected by their physical and chemical properties. While resin-based sealers (AH Plus and EndoREZ) showed a greater depth of penetration, zinc oxide eugenol-based sealer (Tubli-Seal [EWT]) showed the least penetration. The penetration of the polydimethylsiloxane-based sealer (GuttaFlow) was intermediate.

Effect of root canal sealers on bond strength of fibreglass posts cemented with self‐adhesive resin cements

This study evaluated the effects of different root canal sealers on the bond strength of a fibreglass post cemented with self-adhesive resin cements. The root canals of 50 extracted maxillary single-rooted canine teeth were prepared with the crown-down technique and randomly divided into five groups according to the sealer used: group 1: control group, gutta-percha points only (no sealer); group 2: AH Plus (resin-based sealer); group 3: self-etch Epiphany (resin-based sealer); group 4: Sealer 26 (calcium hydroxide-based sealer); and group 5: Endomethasone (zinc oxide eugenol-based sealer). The root canals were filled with gutta-percha, the cold lateral compaction technique, except for group 3 where Resilon was used. Post spaces were prepared, and fibreglass posts were cemented with the self-adhesive cement RelyX Unicem. Bonded specimens were sectioned into 1-mm-thick slabs, and a push-out test was performed in a universal machine. Failure modes were observed and classified into five types: (i) adhesive between the post and resin cement; (ii) mixed, with resin cement covering 0-50% of the post diameter; (iii) mixed, with resin cement covering 50-100% of the post surface; (iv) adhesive between resin cement and root canal; and (v) cohesive in dentine. Data of bond strength were submitted to anova and Tukey test (α = 0.05). No significant difference was detected between control group, AH Plus, Epiphany and Sealer 26 (P > 0.05). The Endomethasone group had significantly lower bond strength values than the other sealers (P < 0.05). The prevalence of mixed fractures and adhesive cement-dentine failure was verified in the eugenol-containing sealer group; in the control group, the resin-based and calcium hydroxide-based sealer groups, the predominant mode of failure was the mixed type. Endomethasone interfered negatively with the bond to root dentine; however, AH Plus, Epiphany and Sealer 26 did not interfere in the bond strength of a fibreglass post cemented with self-adhesive resin cements.