Effect of Ultrasonic Activation of Endodontic Sealers on Intratubular Penetration and Bond Strength to Root Dentin

IntroductionThis study aimed to evaluate the effect of ultrasonic activation (UA) of endodontic sealers on dentin tubule penetration and the bond strength to root dentin.MethodOne hundred single-rooted teeth were prepared with 40.06 nickel-titanium instruments and divided into 2 groups: with or without UA. Three resin-based sealers (MTA Fillapex [Angelus Dental Solutions, Londrina, PR, Brazil], Sealer Plus [MK Life Medical and Dental Products, Porto Alegre, RS, Brazil], and AH Plus [Dentsply, DeTrey GmbH, Konstanz, Germany]; n = 20) and 2 calcium silicate–based sealers (Sealer Plus BC [MK Life Medical and Dental Products] and EndoSequence BC [Brasseler, Savannah, GA], n = 20) were used and subdivided (n = 10) according to the protocols. Fluo-3 (Thermo Fisher Scientific, Waltham, MA) and rhodamine B dyes were added to the calcium silicate- and resin-based sealers, respectively. In the UA groups, the activation was performed for 40 seconds followed by lateral compaction. Samples were transversely sectioned to evaluate the dentin tubule penetration and the bond strength to root dentin. The penetration data were analyzed with the Student t test, 1-factor analysis of variance, and Bonferroni tests. Bond strength was evaluated using the Student t test, Kruskal-Wallis, and Dunn post hoc test.ResultsResin-based sealers showed the highest tubule penetration without UA (P < .05). UA significantly enhanced MTA Fillapex and Endosequence BC dentin tubule penetration (P < .05). AH Plus and Sealer Plus BC improved their bond strength to root dentin after UA (P < .05). AH Plus/UA, Sealer Plus/UA, and Sealer Plus BC/UA presented the highest bond strength values (P < .05). Adhesive failures were predominant in all groups regardless of the use of ultrasound.ConclusionsUA interferes with tubule penetration and the bond strength to root dentin of resin- and calcium silicate–based sealers.     

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.     

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.     

Dentinal tubule penetration of AH Plus,BC Sealer and a novel tricalcium silicate sealer: a confocal laser scanning microscopy study

Objectives

The aim of this in vitro study was to assess the dentinal tubule penetration of three different sealers, AH Plus, BC Sealer and a novel tricalcium silicate sealer (NTS).

Materials and methods

Ninety-six human maxillary central incisors were divided into three experimental groups (n = 32) and were filled with gutta-percha using a single-cone technique in conjunction with one of the three sealers: AH Plus, BC Sealer or NTS. The roots in each group were cross-sectioned at 1 and 5 mm from the root apex, and the surfaces were examined under confocal laser scanning microscopy (CLSM). The sealer penetration depths were measured at their maximum depths and at four circumferential depths (12, 3, 6 and 9 o’clock) and were evaluated using ImageJ software (ImageJ, NIH).

Results

The maximum and mean penetration depths were significantly higher at 5 mm compared to 1 mm from the apex in the AH Plus (p < 0.001), BC Sealer (p < 0.001) and NTS groups (p < 0.001). No significant difference was observed between the groups at 1 mm for both parameters. The maximum and mean penetration depths were significantly lower at 5 mm for AH Plus compared with the other two groups (p = 0.012).

Conclusions

Within the study limitations, the BC Sealer and NTS demonstrated better tubule penetration results than the AH Plus sealer.

Clinical relevance

Although no study has confirmed a relationship between the penetration depth of root canal sealers and the prevention of apical periodontitis, dentinal tubule sealer penetration may improve obturation quality.

     

GuttaFlow Bioseal promotes spontaneous differentiation of human periodontal ligament stem cells into cementoblast-like cells

Objectives

To evaluate in vitro the cementogenic potential and the biological effects of GuttaFlow Bioseal, GuttaFlow 2, MTA Fillapex and AH Plus on human periodontal ligament stem cells (hPDLSCs).

Antifungal activity of several root canal sealers against Candida albicans

Abstract

Objective. The purpose of this in vitro study was to evaluate the antifungal activity of several root canal sealers (iRoot SP, MTA Fillapex and GuttaFlow) against Candida albicans and compare them to that of AH Plus Jet. Materials and methods. A 10 μL fungi in suspension was allowed to directly contact the sealers, which were freshly mixed or allowed to set for 1 or 7 days. Fresh media was then added and survival of fungi was determined by using 10-fold serial dilution and inoculated onto agar plates. After incubation for 48 h, colony-forming units (CFU) were calculated and their log₁₀ values converted. The data were analyzed using ANOVA and Tukey tests (α = 0.05). Results. Freshly mixed AH Plus Jet totally inhibited the growth of fungi and showed the highest antifungal activity. GuttaFlow did not show any significant antifungal activity at all times. Freshly mixed iRoot SP and MTA Fillapex were found to be antifungal. Statistical differences were found between freshly mixed and set samples (p < 0.05) in favor of the former, except GuttaFlow. No statistically significant differences were found among the tested sealers at the 1 and 7-day samples (p > 0.05). Conclusions. Fresh AH Plus Jet had very potent antifungal activity. All sealers, except GuttaFlow, exhibited antifungal activity when freshly mixed.     

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.     

Reciproc and Reciproc Blue in the removal of bioceramic and resin-based sealers in retreatment procedures

Objectives

To compare the remaining root canal filling material, dentin removal, apical transportation, and apical extrusion of debris after the retreatment of canals filled with bioceramic or resin-based sealers using the Reciproc or Reciproc Blue instruments.

Materials and methods

Sixty mandibular molars with severely curved mesial roots were selected. The samples were initially instrumented with Reciproc (R25) and then divided into four experimental groups according to the endodontic sealer and retreatment instrument (n = 15): BC Sealer/Reciproc (BCRC), BC Sealer/Reciproc Blue (BCRB), AH Plus/Reciproc (AHRC), and AH Plus/Reciproc Blue (AHRB). The procedure time was measured, and an Eppendorf tube was used in each root canal to store the debris extrusion. The samples were scanned by micro-CT before and after retreatment. The apical transportation, volume of dentin, and filling material were evaluated.

Results

There were no significant differences in the reduction of the volume of obturator material or dentin removal between groups (p > .05). There were also no differences in the amount of extruded material or apical transportation (p > .05). The retreatment time for the AHRC group was significantly lower than that for the other groups (p = .004).

Conclusions

All tested instruments obtained similar efficacy in filling material removal procedures, although no system completely removed the filling material. Retreatment of canals filled with bioceramic BC Sealer may be more time consuming.

Clinical relevance

This study reported that Reciproc and Reciproc Blue can be indicated in retreatment of severely curved root canals filled either with bioceramic or resin-based sealers.

     

Volume and Power of Expansion of Novel Polyurethane-based Sealers

IntroductionShrinkage and lack of interfacial adaptation between endodontic sealers and root canal walls may jeopardize the root canal treatment outcome. This study aimed to evaluate the volume and power of expansion (and the relationship between the two) of three novel root canal sealers (polyurethane expandable sealer [PES], zeolite + PES [ZPES], and elastomeric polyurethane sealer [EPS]) in comparison with an epoxy-resin based sealer (AH Plus) and a calcium silicate-based sealer (EndoSequence BC).MethodsThis study utilized 36 cylinders (30 plastic graduated cylinders for volume of expansion and 6 steel cylinders for power of expansion) (4 × 10 mm) filled with PES, ZPES, EPS, AH Plus, EndoSequence BC, or water (n = 5/group). The plastic graduated cylinders were inserted inside a customized Linear Swell Meter apparatus to measure the percentage of volumetric expansion. The steel cylinders were placed inside a Linear Swell Meter apparatus mounted onto a universal testing machine to measure the maximum pressure in psi. Specimens were tested for 72 hours for both volume and power of expansion tests. Data were analyzed using Kolmogorov-Smirnov, one-way ANOVA, Post Hoc Tukey, and Pearson correlation tests (P < .05).ResultsThe volume of expansion of PES, ZPES, and EPS was significantly higher than in AH Plus and EndoSequence BC (P < .05). For the power of expansion, no significant differences were found between the root-filling materials (P > .05). No correlation was seen between the volume and power of expansion (P > .05).ConclusionAlthough polyurethane-based sealers showed a significantly higher volume of expansion compared to AH Plus and EndoSequence BC, their power of expansion did not increase significantly.     

Effect of calcium silicate-based endodontic sealer on the retention of fiber posts cemented at different time intervals

ObjectiveTo evaluate the effect of BC HiFlow, a new calcium silicate-based endodontic sealer, compared with a resin epoxy-based sealer after 2 different times of cementation on the pull-out bond strength of glass-fiber–reinforced composite posts cemented with a self-adhesive resin cement (RelyX Unicem).MethodologySixty human maxillary central incisors were decoronated, prepared and obturated with gutta-percha and sealer. Roots were distributed into 5 groups according to the sealer and time of post cementation: (1) AH Plus sealer with immediate post fixation, (2) BC HiFlow with immediate post fixation, (3) AH Plus and post fixation after 7 days, (4) BC HiFlow and post fixation after 7 days, and (5) fiber post fixation in canals obturated with gutta-percha only (no sealer). After 1 week of post cementation, the pull-out test was performed and the failure mode was examined under a digital microscope. Data were analyzed using ANOVA followed by Tukey's post hoc and t tests (p < .05).ResultsWith immediate post cementation, AH Plus group showed significantly higher pull-out retentive strength than the BC HiFlow and control groups (p = .009 and p < .001, respectively). There was no significant difference between the groups when the posts were cemented 7 days after obturation (p = .726). The time of post cementation had a significant influence on the canals obturated with AH Plus (p = .003). The time did not significantly affect the canals obturated with BC HiFlow (p = .289). The prominent type of failure was mixed mode in all groups.ConclusionBC HiFlow sealer did not affect the pull-out bond strength of glass-fiber–reinforced composite posts cemented with a self-adhesive resin cement immediately after or 7 days after obturation. For immediate post cementation, AH Plus increased the pull-out bond in comparison to BC HiFlow.     

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.     

Assessment of Root Canal Sealers Loaded with Drug-Silica Coassembled Particles Using an In Vitro Tooth Model

IntroductionThe purpose of this study was to assess the antimicrobial activity of root canal sealers modified with novel highly loaded antimicrobial drug-silica coassembled particles (DSPs) on Enterococcus faecalis–infected root canal dentin.MethodsDSPs were synthesized through coassembly of silica and octenidine dihydrochloride (OCT) surfactant drug (35% w/w OCT). DSPs (1% wt of the total mass of the sealer) were mixed homogenously with either epoxy resin sealer (AH Plus [AH]; Dentsply Sirona, Tulsa, OK) or calcium silicate–based sealer (EndoSequence BC Sealer [BC]; Brasseler, Savannah, GA). To assess the antimicrobial activity of DSP-loaded sealers, the apical third of single-rooted teeth was obtained and infected with E. faecalis for 3 weeks followed by the application of experimental (DSP-loaded) sealers or corresponding controls for up to 28 days. Microbiological analysis and laser scanning confocal and scanning electron microscopy were used to determine the colony-forming unit (CFU)/mL, the percentage of live bacteria, and the intratubular bacterial and sealer penetrations. Factorial analysis of variance and Tukey post hoc tests were used to assess the antimicrobial effect of DSPs on different sealers.ResultsAll experimental groups showed significant reductions in CFUs at all-time points compared with positive controls (P < .05). The addition of DSPs to BC significantly reduced the CFUs (2.11 ± 0.13, 2.22 ± 0.19, and 2.25 ± 0.17 at 1, 7, and 28 days, respectively) compared with the unmodified sealer (3.21 ± 0.11, 4.3 ± 0.15, and 4.2 ± 0.2 at 0, 7, and 28 days). DSPs enhanced the antimicrobial performance of AH only at 1 day (4.21 ± 0.17 vs 5.19 ± 0.12, P < .05). AH and AH + DSPs showed higher bacterial viability compared with BC and BC + DSPs at all incubation periods (P < .05).ConclusionsLoading endodontic sealers with DSPs had a material-dependent effect on the antimicrobial properties and could reduce the incidence of secondary infections.     

Antimicrobial and physicochemical characterization of endodontic sealers after exposure to chlorhexidine digluconate

ObjectivesAssess the antibacterial, physical and chemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) in contact with 2% chlorhexidine digluconate (CHX) used as final irrigant prior to root canal obturation.MethodsThe antimicrobial properties were investigated by direct contact tests for planktonic and biofilm growth of E. faecalis, S. mutans, S.epidermidis and S.aureus in vitro. The setting time, wettability, microhardness and surface roughness were also assessed. The sealers were studied in no contact, 1-minute (short-term) and continuous contact (long-term) with CHX. Chemical characterization of sealers was performed by scanning electron microscopy, X-ray diffraction analysis and Fourier-transform infrared spectroscopy after CHX or saline used as the last irrigant in an ex vivo tooth model and in endo training blocks.ResultsCHX increased the antibacterial activity of all the sealers investigated against planktonic bacteria and biofilms with PCS exerting the highest antimicrobial activity with and without the presence of CHX. The setting of AH Plus and BioRoot RCS was retarded, while for PCS accelerated in the presence of CHX. AH Plus and PCS were more hydrophilic after contact with CHX, whilst BioRoot RCS was hydrophobic in a time-dependent manner. The microhardness of sealers was compromised and the surface roughness increased after CHX exposure for AH Plus and BioRoot RCS, and decreased for PCS. CHX did not affect the sealers’ chemistry, but PCS that exhibited two extra phases.SignificanceCHX improved the antibacterial efficacy of endodontic sealers but further evidence is needed to confirm its suitability as a final irrigant prior to root canal obturation.     

Hydroxyapatite-based cements induce different apatite formation in radicular dentin

ObjectiveTo investigate crystallinity and ultrastructure of the formed hydroxyapatite at radicular cervical and apical dentin after being treated with three different canal sealers.MethodsCervical and apical root dentin surfaces were treated with two experimental hydroxyapatite-based sealers, containing sodium hydroxide (calcypatite) or zinc oxide (oxipatite) and an epoxy resin-based canal sealer (AH Plus); gutta-percha without sealer was included as control. Dentin surfaces were studied by X-ray diffraction and transmission electron microscopy through selected area diffraction and bright-field imaging after 24 h and 12 m of storage.ResultsRoot cervical dentin treated with calcypatite and oxipatite produced poor crystallinity of new minerals, wide amorphous phase and non-stoichiometry. Reflections at the 002 plane and the corresponding diffraction rings attained lower values in the Scherrer equation and the Scherrer-Wilson equation in samples treated with both HAp-based sealers than in specimens without sealer or with AH Plus. At root cervical dentin treated with calcypatite, shorter and wider crystallite size formations and lower crystals grain size were found, if compared to those encountered at oxipatite treated dentin. Oxipatite attained improved crystallographic atomic order and less structural variation in both distances and angles. Apical dentin treated with oxipatite attained preferred grain orientation with polycrystalline lattices.SignificanceThe immature crystallites formed in dentin treated with calcypatite and oxipatite will account for high hydroxyapatite solubility and remineralizing activity. New polycrystalline formations encountered in apical dentin treated with oxipatite may also produce high mechanical performance.     

In vitro evaluation of the antibacterial effect of four root canal sealers on dental biofilms

Objectives

To dynamically evaluate the effect of four root canal sealers on the killing of biofilms within dentinal tubules.

Materials and methods

Dentin blocks were prepared for infection of the dentinal tubules. Enterococcus faecalis VP3-181 and multi-species bacteria from two donors were cultured. After 3 days of incubation, the infected dentin specimens were rinsed with sterile water for 1 min and subjected to treatment. Additionally, multi-species bacteria from donor 1 were incubated for 3 weeks to allow biofilm maturation and then the specimens were subjected to treatment. Gutta-percha-treated dentin specimens comprised the control group. A root canal sealer (bioceramic sealers: EndoSequence BC Sealer, ProRoot Endo Sealer, or GuttaFlow Bioseal; and a traditional silicone-based sealer: Guttaflow 2) was spread onto the canal walls of the dentin. The specimens were examined with confocal laser scanning microscopy at 7, 30, or 60 days.

Results

In the 3-day-old biofilm group, the proportion of killed bacteria decreased significantly from the first 7 days of treatment to 60 days of treatment for all sealers (p?<?0.05). In the 3-week-old biofilm group, 60 days of exposure to bioceramic sealers resulted in more significant dead bacteria than 7-day exposures of the biofilms (p?<?0.05). Bioceramic sealers were more effective in killing bacteria than the GuttaFlow 2 sealer (p?<?0.05).

Conclusions

Calcium silicate–based sealers showed good antimicrobial effects against biofilms within dentinal tubules, especially in the first week in young biofilms. There is no substantive antibacterial activity observed for the examined root canal sealers against young dentinal tubule biofilms.

Clinical relevance

The bioceramic root canal sealers examined demonstrate minimal additional antibacterial effects after long-term exposure to young biofilms.

     

Water sorption and solubility of methacrylate resin-based root canal sealers

The water sorption and solubility characteristics of three contemporary methacrylate resin-based endodontic sealers, EndoREZ, Epiphany, and InnoEndo, were compared with those obtained from Kerr EWT, Ketac-Endo (positive control), GuttaFlow, and AH Plus (both negative controls). Ten disks of each material were dehydrated in Drierite for 24 h and weighed to constant dry mass. They were placed in water and weighed periodically until maximum water sorption was obtained. The disks were dehydrated again to determine their mass loss (solubility) at equilibrium. Epiphany exhibited the highest apparent water sorption (8%) followed by Ketac-Endo (6.2%), InnoEndo (3.4%), EndoREZ (3.0%), AH Plus (1.1%), GuttaFlow (0.4%), and Kerr EWT (0.3%). Significantly higher solubility (3.5-4%) were observed for all three methacrylate resin-based sealers and Kerr EWT (3.95%), compared with Ketac-Endo (1.6%), AH Plus (0.16%), and GuttaFlow (0.13%). American Dental Association specifications require<3% solubility for endodontic sealers. Only Ketac-Endo, AH Plus, and GuttaFlow met that criterion.     

Physical Properties of 5 Root Canal Sealers

Introduction

The aim of this study was to evaluate the pH change, viscosity and other physical properties of 2 novel root canal sealers (MTA Fillapex and Endosequence BC) in comparison with 2 epoxy resin-based sealers (AH Plus and ThermaSeal), a silicone-based sealer (GuttaFlow), and a zinc oxide-eugenol–based sealer (Pulp Canal Sealer).

Methods

ISO 6876/2001 specifications were followed. The pH change of freshly mixed and set sealers was evaluated during periods of 1 day and 5 weeks, respectively. The viscosity was investigated at different injection rates (72, 10, and 5 mm/min) at room temperature by using a syringe-based system that was based on the Instron 3360 series universal testing system.

Results

The flow, dimensional change, solubility, and film thickness of all the tested sealers were in agreement with ISO 6876/2001 recommendations. The MTA Fillapex sealer exhibited a higher flow than the Endosequence BC sealer (P < .05). The MTA Fillapex and Endosequence BC sealers showed the highest film thicknesses among the tested samples. The Endosequence BC sealer exhibited the highest value of solubility, which was in accordance with 3% mass fraction recommended by the ISO 6876/2001, and showed an acceptable dimensional change. The MTA Fillapex and Endosequence BC sealers presented an alkaline pH at all times. The pH of fresh samples of the AH Plus and ThermaSeal sealers was alkaline at first but decreased significantly after 24 hours. The viscosity of the tested sealers increased with the decreased injection rates.

Conclusions

The tested sealers were pseudoplastic according to their viscosities as determined in this study. The MTA Fillapex and Endosequence BC sealers each possessed comparable flow and dimensional stability but higher film thickness and solubility than the other sealers tested.     

A Novel GuttaFlow Sealer Supports Cell Survival and Attachment

Introduction

The purpose of this in vitro study was to compare the biocompatibility of a novel formulation of a silicone-based endodontic sealer GuttaFlow 2 (GF2; Coltène/Whaledent, Langenau, Germany) with the original (GFO) and fast-set (GFF) formulations of GuttaFlow and with an epoxy resin sealer, AHPlus Jet (AH+J; Dentsply, York, PA).

Methods

Sealers were set into 3 × 5.5 mm discs. Cell culture media was used to extract leachable products at 24 hours and 1, 2, and 4 weeks. Primary human periodontal ligament fibroblasts were incubated with sealer elutes for 24 hours and evaluated using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay and the calcein AM assay. Cell attachment was evaluated on set sealer that was either rinsed or unrinsed with cell media for 1 week. Statistical analysis was performed using the Student t test.

Results

Both calcein and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assays revealed that periodontal ligament cell viability was reduced on AH+J at 1, 2, and 4 weeks compared with all GuttaFlow sealers. There were no differences in cell viability between the GuttaFlow samples, and all displayed high rates of cell survival at all time periods. After 2 hours, cell attachment to the rinsed GFO and GFF samples exceeded the control, and at 24 hours cell attachment on all GuttaFlow samples exceeded the control. AH+J sealers supported significantly less cell attachment when compared with all GuttaFlow sealers. Cell attachment to set sealers showed better cell attachment when rinsed compared with unrinsed.

Conclusions

GuttaFlow sealers were more biocompatible than AHJ in vitro. The novel GF2 displayed comparable biocompatibility with GFF and GFO.     

Clinical Efficacy of Sealer-based Obturation Using Calcium Silicate Sealers: A Randomized Clinical Trial

IntroductionThis randomized controlled clinical trial compared the clinical efficacy and outcome of a sealer-based obturation technique (SBO) with calcium silicate sealers and a continuous wave of condensation technique (CWC) with a resin-based sealer.MethodsRoot canals were prepared using rotary instruments and 2.5% sodium hypochlorite. At the next visit, patients were enrolled and randomly assigned into 2 groups on the basis of the obturation protocol: CWC with AH Plus sealer and SBO with Endoseal TCS. Patients were assessed for the level of postoperative pain using a numeric rating scale. The quality of root canal obturation was evaluated in terms of the sealer extrusion, root-filling voids, and level of root filling. The participants were recalled after at least 6 months. Healing of the teeth was determined as a decrease in Periapical Index score and resolution of symptoms. The results were statistically compared by using the χ² test or Fisher exact test, followed by multivariate analysis with logistic regression.ResultsA total of 74 teeth were included in the analysis (79% recalls), and the mean follow-up period was 17 months (6–29 months). Two groups expressed identical distribution of postoperative pain (P = .973) and similar quality of root canal obturation. The total success rates were 93.2% (CWC 92.3%, SBO 94.3%) by loose criteria and 60.8% (CWC 51.3%, SBO 71.4%) by strict criteria, with no significant differences between the 2 groups. The success rate by loose criteria in teeth with sealer extrusion was significantly lower than those in teeth without sealer extrusion (P = .049).ConclusionsSBO using an Endoseal TCS could be a possible alternative to CWC using AH Plus. Sealer extrusion and postoperative pain were found to negatively impact prognosis of the endodontic treatment.