Brasseler USA Research Articles

EFFECTS OF MTAD ON THE BOND STRENGTH OF BIOCERAMIC ROOT CANAL SEALER

Aim: The aim of this in-vitro study was to investigate the effects of MTAD (a mixture of doxycycline, citric acid, and a detergent) on the bond strength of AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) and EndoSequence BC sealer (Brasseler USA, Savannah, Georgia, USA). Materials & Methods: Eighty-four decoronated single-rooted human incisor teeth were prepared with Reciproc R25 files (VDW, Munich, Germany), and the canal was irrigated with 5 mL 1.3% NaOCl. The roots were randomly assigned to four groups (n = 21), according to the final irrigation protocol and sealer selection: Group 1: distilled water-AH Plus; Group 2: distilled water-EndoSequence BC; Group 3: MTAD-AH Plus; Group 4: MTAD-EndoSequence BC. For the final flush, in Groups 1 and 2, the root canals were irrigated with 5mL of distilled water; in Groups 3 and 4, 5mL of MTAD was used for 1 minute. After root canal obturation, specimens was embedded in an acrylic block and sectioned horizontally at three levels (coronal, middle, apical). Bond strength of sealer to root canal dentin was assessed via push-out test using a universal testing machine. Results: There were no significant differences among the groups in coronal and apical thirds. In the middle root third, Group 4 showed significantly lower push-out bond strength values than Group 2 (p=0.023). No significant difference was found between the two root canal sealers. Conclusions: Overall, MTAD final irrigation caused lower push-out bond strenght values than distilled water with no significancy.

Retrospective Analysis of Root-end Microsurgery Outcomes in a Postgraduate Program in Endodontics Using Calcium Silicate–based Cements as Root-end Filling Materials

IntroductionThe purpose of this retrospective study was to determine the clinical and radiographic outcomes of root-end microsurgery in a postgraduate program in endodontics using modern techniques and calcium silicate–based root-end filling materials (ProRoot MTA; Dentsply International, Johnson City, TN, and EndoSequence Root Repair Material [ERRM]; Brasseler USA, Savannah, GA) and to identify any potential prognostic factors that may have affected healing outcomes. MethodsClinical records and periapical radiographs were collected from patients who had undergone endodontic microsurgery between 2007 and 2018 in a postgraduate endodontic clinic with a minimum follow-up interval of 6 months. Either ProRoot MTA or ERRM was used as the root-end filling material. Outcomes were categorized into healed, healing, and nonhealing based on clinical and radiographic findings. Healed and healing cases were pooled and considered as successes, whereas nonhealing cases were considered as failures. ResultsA total of 129 patients with 142 teeth were included in the final analysis. Seventy-six cases were root-end filled with ProRoot MTA and 66 root-end filled with ERRM. The ProRoot MTA group had a success rate of 92.1%, and the ERRM group had a success rate of 92.4% with no significant difference between the groups (P > .05). Vertical root fracture was found to be the predominant cause of failure. No patient- or treatment-related factor was identified to have any significant impact on healing. ConclusionsHigh overall success can be achieved in a postgraduate endodontic program when either ProRoot MTA or ERRM is used as the root-end filling material.

Shear Bond Comparison between 4 Bioceramic Materials and Dual-cure Composite Resin

IntroductionBioceramic materials have shown biologic and physical properties favorable for regenerative treatment. A key to treatment success is an adequate restoration to prevent microleakage; however, research is limited regarding the bond strength between restorative and bioceramic materials used in regenerative procedures. This study compared the bond strength between 4 bioceramic materials and a dual-cure composite resin. MethodsEighty wells in Teflon (ePlastics, San Diego, CA) blocks were filled with bioceramic materials representing 4 groups: White ProRoot mineral trioxide aggregate (MTA) (Dentsply Tulsa Dental, Tulsa, OK), Biodentine (Septodont, Saint Maur des Fosses, France), EndoSequence Root Repair Material Fast Set Putty (Brasseler USA, Savannah, GA), and NeoMTA (Avalon Biomed Inc, Houston, TX). After allowing samples to set according to the manufacturers’ instructions, exposed surfaces of the bioceramic materials were prepared using ClearFil SE Bond (Kuraray America, Inc., New York, NY) followed by restoration with ClearFil DC Core Plus (Kuraray America, Inc.). To test shear bond strength, each block was secured in a universal testing machine, and the crosshead was advanced at 0.5 mm/min until fracture. Newton peak force was recorded and megapascals calculated followed by data comparison. ResultsThe mean shear bond strengths between ClearFil DC Core Plus and the bioceramic materials were as follows: White ProRoot MTA, 7.96 MPa; Biodentine, 9.18 MPa; EndoSequence Root Repair Material Fast Set Putty, 4.47 MPa; and NeoMTA, 5.72 MPa. White ProRoot MTA and Biodentine were statistically similar, with a higher stress bond strength than NeoMTA, which had a statistically greater bond strength than EndoSequence Root Repair Material. All these values were lower than typical bond strengths shown for dentin–composite resin bonding. ConclusionsThe choice of which bioceramic material to use in regenerative procedures should be based on factors other than the bond between that material and the overlying coronal resin restoration.

Dentinal Tubule Penetration and Retreatability of a Calcium Silicate–based Sealer Tested in Bulk or with Different Main Core Material

IntroductionThe aim of this study was 2-fold: to evaluate the penetration of a tricalcium silicate–based endodontic sealer (EndoSequence BC Sealer; Brasseler USA, Savannah, GA) into dentinal tubules without a core material (sealer) or with .02 or .04 tapered bioceramic gutta-percha points and to compare the time required to remove the root fillings . MethodsRoots of extracted human mandibular incisors (N = 60) were prepared with 0.04 taper nickel-titanium rotary files to #35 and randomly assigned into 3 groups (n = 10/group) according to the obturation method used:1. obturating with sealer only,2. sealer + .02 point, and3. sealer + .04 point. The sealer was labeled with rhodamine B for analyzing dentinal tubule penetration under a confocal laser scanning microscope. The remaining specimens (n = 30) were used to measure the time for removal of the root canal fillings with retreatment files. The data were analyzed using 1-way analysis of variance and post hoc Games-Howell tests for dentinal tubule penetration and the Kruskal-Wallis test for retreatment time. ResultsSignificantly greater sealer penetration and sealer-penetrated area was achieved when the sealer was used with a .04 gutta point (P < .05), whereas there was no difference between the sealer and .02 gutta point groups (P > .05). All test groups showed a similar depth of sealer penetration (P > .05). Groups with the gutta-percha points required a similar time to remove root filling (P > .05), whereas the working length could not be achieved in the sealer group. ConclusionsThe use of a matched-taper bioceramic gutta-percha point enhanced the dentinal tubule penetration of the tested tricalcium silicate–based sealer. The use of a core material in conjunction with sealer facilitates removal of the root filling to the working length.

Treatment of a root canal perforation using a calcium-silicate based sealer: a case report with a 4 year follow-up

Aim: This case report presents a root canal retreatment distinguished by a canal perforation successfully treated with a calcium-silicate based sealer (EndoSequence BC sealer, Brasseler USA, Savannah, GA, USA) with a 4 year follow-up. Summary: Root canal retreatment of a lower left second molar was performed in 80 years old patient because of a periapical chronic periodontitis with buccal fistula. The scouting of the mesio-lingual and distal canal was obtained with a k-file #10, while the mesio-buccal was not negotiable because of a perforation in the middle third of the root. Instrumentation of patent root canal was performed and the distal canal was filled with AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) and Thermafil Obturator (Dentsply Maillefer, Ballaigues, Switzerland) whereas the mesial canals and the per foration were sealed using EndoSequence BC Sealer and dedicated EndoSequence BC Points in order to perform a successive apical surgery. The improvement of clinical conditions and, successively, the gradual bone healing, confirmed with analogical radiographs, led to avoid the complicated endodontic surgery on this lower second molar, having already an acceptable clinical success. Key Learning Points: This case report confirmed the favorable physical and biological properties of calcium-silicate based sealers and, most of all, the handling properties of the EndoSequence BC sealer. In selected cases these type of sealers might lead to resolve complex treatments without using specialistic equipments like microscope and help general clinicians to approach complicated endodontic cases in an easier way.

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.

Bone tissue response to an MTA-based endodontic sealer, and the effect of the addition of calcium aluminate and silver particles.

To evaluate bone tissue reactions in rats to an MTA-based endodontic sealer with and without the addition of various concentrations of C3A or C3A+Ag. Bone tissue reactions were evaluated in 45 Wistar rats after 7, 30 and 90days (n=5 per period). Three surgical cavities were prepared on the right femur and filled with 0.2 mL MTA Fillapex, MTA Fillapex+C3A and C3A+Ag at various concentrations: AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany), EndoSequence BC (Brasseler USA, Savannah, GA, USA) or no sealer (negative control). By the end of each experimental period, animals were randomly euthanized. The samples were histologically processed and analysed using a light microscope. The presence of inflammatory cells, fibres and hard tissue barrier formation was evaluated. Data were analysed statistically using nonparametric tests to compare the differences between groups. Multiple groups were compared using the Kruskal-Wallis and Mann-Whitney U-tests with a Bonferroni correction at P=0.05. The inflammatory response significantly decreased from 30 to 90days (P<0.05). Fibre condensation was similar amongst the groups at 07 and 30days after intervention (P>0.05). At 90days, however, fibres were absent in most specimens of EndoSequence BC Sealer, AH Plus, MTA Fillapex and the control group, whilst they were still observed in samples of the modified sealers (P<0.05). At 90 days, all specimens of AH Plus, EndoSequence BC Sealer and control group had complete formation of hard tissue barrier. In the MTA Fillapex group, as well as in the modified sealers groups, partial deposition of mineralized tissue was noticed. The hypothesis tested that the incorporation of C3A and C3A+Ag particles to MTA Fillapex would improve bone tissue repair was partially accepted, since modified MTA Fillapex did not have the same repair potential as the commercial bioceramic material.

Micro‐XRD and nanoindentation investigation of bioceramics for dental pulp therapy

AbstractTherapeutic bioceramics for dental pulp treatment are an area of active research. This study investigated the phases in two commonly used bioceramics and depth of dentin remineralization after application of these bioceramics. Cavities in non‐carious third molars were filled with ProRoot White mineral trioxide aggregate (MTA) (Dentsply Tulsa Dental), EndoSequence Root Repair Material (Brasseler USA) and with calcium hydroxide (Dycal, Dentsply Caulk) serving as a control. Specimens were immersed in simulated body fluid (SBF) for 3 months, and Micro‐X‐ray diffraction (Micro‐XRD) analyses were performed on the bioceramics two minutes after placement and at seven subsequent intervals. After three months in SBF, specimens were subjected to nanoindentation testing. Micro‐XRD revealed the presence of dicalcium silicate, tricalcium silicate, tricalcium aluminate and calcium sulphate in both bioceramics. Opacifying agents bismuth oxide and zirconia were also detected in ProRoot White MTA and EndoSequence Root Repair Material, respectively. There was no evidence for the silicate gel matrix that forms during setting of these bioceramics. Nanoindentation testing revealed that at &lt;17 µm from the interface, the nanohardness of dentin in specimens filled with Dycal was lower than for EndoSequence and ProRoot White MTA, whereas at 21–97 µm from the interface, there was no significant difference in nanohardness of dentin filled with any material.

Improved sealing ability promoted by calcium silicate-based root canal sealers

Aim: This study investigated the sealing ability produced by AH Plus (Dentsply DeTrey, Konstaz, Germany), EndoSequence BC sealer (Brasseler USA, Savannah, GA, USA), GuttaFlow (Coltène/Whaledent, Altstätten, France) and MTA Fillapex (Angelus, Londrina, Brazil). Methdos: A total of forty-six single-root human canines were prepared and randomly divided into four experimental groups (n=10): MTA Fillapex, EndoSequence BC Sealer, AH Plus or GuttaFlow. Teeth with intact crowns served as negative controls (n=3) and teeth filled with only gutta-percha served as positive controls (n=3). Teeth were mounted in a two-chamber apparatus and exposed to Enterococcus faecalis. The number of days over a 60-days period was recorded for the appearance of turbidity in the lower chamber. Kaplan-Meier method was used to estimate the survival curves. The nonparametric log-rank test was used to compare the survival curves using a significance level of 0.05. Results: The results at the end of the observation time were further analyzed by chi-square testing. All positive controls leaked within 24 h, whereas none of the negative controls leaked after 60 days. EndoSequence BC Sealer and MTA Fillapex had significant less bacterial leakage (P&lt;0.05) than the other tested sealers. No significant difference between AH Plus and GuttaFlow was observed (P&gt;0.05). Conclusion: In conclusion, calcium-silicate based root canal sealers promoted improved sealing ability when compared to other endodontic sealers.

Clinical Outcome of Non-Surgical Root Canal Treatment Using a Single-cone Technique with Endosequence Bioceramic Sealer: A Retrospective Analysis

IntroductionOne of the important steps in root canal treatment is to create a well-sealed root canal system. EndoSequence BC Sealer (BC; Brasseler USA, Savannah, GA) has several beneficial properties and thus has been incorporated into the practitioner's armamentarium. No studies to date have evaluated the clinical success of using BC. The purpose of this study was to evaluate the outcome of nonsurgical root canal treatment using a single-cone and BC technique and to identify factors associated with success or failure. MethodsThis retrospective cohort study included patients treated in a private practice environment between 2009 and 2015. All cases, including initial and retreatment, were obturated with BC using a single-cone technique with a minimum of a 1-year recall. Patient and treatment factors were analyzed to determine their significance as prognostic factors. Outcome was evaluated based on clinical and radiographic findings at recall. Teeth were classified as healed, healing (success), or not healed (failure). Statistical analysis of potential prognostic factors was performed using the chi-square test (α = 0.05). ResultsThree hundred seven teeth were included in the analysis, and the average follow-up time was 30.1 months. The overall success rate was 90.9%. Lesions <5 mm in diameter had a significantly higher success rate than lesions >5 mm in diameter. Sealer extrusion was observed in 47.4% of the cases. The presence of sealer extrusion did not have any significant effect on the treatment outcome. ConclusionsBC used with a single-cone technique is a viable option for obturation.

Evaluation of Biocompatibility and Osteogenic Potential of Tricalcium Silicate–based Cements Using Human Bone Marrow–derived Mesenchymal Stem Cells

IntroductionThe success of endodontic regeneration lies in the appropriate combination of stem cells and bioactive materials. Several novel dental materials are available on the market in this regard. Hence, the current study aimed to evaluate the proliferation, differentiation, and osteogenic potential of human bone marrow–derived mesenchymal stem cells (hBMSCs) onto biomaterials like ProRoot MTA (MTA; Dentsply Tulsa Dental, Tulsa, OK), Biodentine (BD; Septodont, Saint Maur de Fosses, France), and EndoSequence Root Repair Material (ERRM; Brasseler USA, Savannah, GA). MethodsDental cements were formulated into discs and assessed for their biocompatibility. hBMSCs were used to study biocompatitibility and the proliferative and osteogenic potential of these dental cements. A live dead assay was performed using confocal microscopy to study the biocompatibility, proliferation, and cell attachment property of the cements. An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was also performed on days 1, 3, 5, and 7 to study growth kinetics. The osteogenic potential of these cements was studied by inducing hBMSCs over them using osteogenic differentiation medium (assessed by alkaline phosphatase assay). ResultsERRM and MTA have shown the best biocompatibility among the tricalcium silicate materials used with no significant difference between them. Both have shown significantly higher osteogenic bioactivity than BD. All 3 tricalcium silicate cements support good adherence of hBMSCs. ConclusionsAll of the dental cements used in this study are biocompatible with the potential to induce proliferation and osteogenic differentiation of hBMSCs. Therefore, the newly introduced ERRM can be the material of choice in various endodontic applications.

Low Environmental Temperature Influences the Fatigue Resistance of Nickel-titanium Files

IntroductionThe purpose of this study was to evaluate the effect of different temperatures (0°C, 10°C, 22°C, 37°C, and 60°C) on the cyclic fatigue life of nickel-titanium (NiTi) files using a new fatigue test model in zirconium oxide. MethodsThree superelastic NiTi files (EndoSequence [Brasseler USA, Savannah, GA], ProFile [Dentsply Tulsa Dental Specialties, Tulsa, OK], and K3 [SybronEndo, Orange, CA]), and 3 heat-treated (K3XF [SybronEndo], Vortex [Dentsply Tulsa Dental Specialties], and HyFlex CM [Coltene-Whaledent, Allstetten, Switzerland]) NiTi files, all size 25/.04, were subjected to cyclic fatigue tests inside a novel, artificial ceramic canal with a curvature of 60° and a 5-mm radius. The model was immersed in water at 5 different preset temperatures. The number of cycles to failure (NCF) was recorded, and the fracture surface of the fragments was examined by a scanning electron microscope. The data were analyzed using 2-way analysis of variance with the significance level at 0.05. ResultsWhen the temperature was reduced from 60°C to 0°C, the NCF significantly increased from over 2 to 10 times for the NiTi file groups (P < .01). K3XF had the highest fatigue resistance of all files at 0°C (P < .05). Vortex files had the highest NCF at 10°C–60°C. The NCF of heat-treated files was significantly higher than superelastic NiTi files at 10°C and 20°C (P < .05). There was no significant difference in the NCF of HyFlex CM at 0°C and 22°C. There was little difference in the fractographic appearance among different temperatures, except that the fraction area occupied by the dimple region of some instruments at 0°C was slightly smaller than at 60°C. ConclusionsCooling down to low temperatures may be an interesting strategy to improve the fatigue resistance of rotary NiTi files.

Different Setting Conditions Affect Surface Characteristics and Microhardness of Calcium Silicate-Based Sealers.

Objective To investigate the effect of different setting conditions on surface microhardness and setting properties of calcium silicate-based sealers. Methods Three sealers, EndoSequence Bioceramic (BC; Brasseler USA, Savannah, GA, USA), Endoseal MTA (ES; Maruchi, Wonju, Korea), and Well-Root ST (WR; Vericom, Chuncheon, Korea), were compared. Specimens were exposed to either butyric acid (pH 5.4) or phosphate-buffered saline (PBS [pH 7.4]) for 48 h and stored at 100% humidity for 12 days. The control specimens were stored at 100% humidity for 14 days. Surface microhardness was measured, topographic changes were observed, and phase analysis was performed using X-ray diffraction. Microhardness according to storage conditions was compared using one-way analysis of variance and Tukey's multiple comparison tests (P < .05). Results The BC and ES sealers exhibited decreased microhardness when stored in acid or PBS compared with control (P < .05). In the WR group, acid exposure lowered microhardness of the specimens compared with control (P < .05). Scanning electron microscopy revealed different topographies in specimens from all tested sealers exposed to acid or PBS. Conclusion The surface microhardness of calcium silicate-based sealers was reduced by exposure to either acid or PBS. Acid solutions, however, had a more detrimental effect than PBS.

Assessment of Volumetric Distortion Artifact in Filled Root Canals Using Different Cone-beam Computed Tomographic Devices

IntroductionArtifacts in cone-beam computed tomographic (CBCT) imaging may compromise radiodiagnosis. Obturation materials for endodontic treatment may present with variable material density and thus also cause distinct artifact expression. The aim of this study was to assess the volume distortion artifact of root canal sealers using CBCT devices and micro-CT imaging as a reference. MethodsThirty single-root mandibular central incisors were used for this study. Teeth were prepared with EndoSequence rotary nickel-titanium files (Brasseler USA, Savannah, GA) and divided into 3 groups. Canals were obturated with gutta-percha and AH Plus root canal sealer (Dentsply Maillefer, Ballaigues, Switzerland) using single-cone filling techniques. Each tooth was scanned with different CBCT devices (ie, Promax 3D Max [Planmeca Inc, Roselle, IL], NewTom VGi evo [NewTom, Verona, Italy], and 3D Accuitomo 170 [J Morita, Kyoto, Japan]) with the same voxel size (0.2 mm3) and compared with micro-CT imaging as a reference standard. ResultsThe results showed a significant difference in terms of volume distortion between micro-CT and CBCT images (P < .05). There were also significant differences among CBCT devices. Promax 3D Max measurements showed significantly larger root canal volumes than the other CBCT machines (P < .05). However, NewTom VGi evo and 3D Accuitomo 170 showed similar results without any significant difference (P > .05). ConclusionsCBCT devices showed more volumetric distortion artifact than micro-CT imaging. The volume was variable for different CBCT devices while scanning at the same voxel size. However, to assess the effect of sealer materials on CBCT imaging, further studies should be conducted for different sealers.

The Effect of Temperature on Cyclic Fatigue of Nickel-titanium Rotary Endodontic Instruments

IntroductionThis study examined the effect of different temperatures on the cyclic fatigue of nickel-titanium rotary files. MethodsThree groups of nickel-titanium rotary files (EF group [EdgeFile; EdgeEndo, Albuquerque, NM], VB group [Vortex Blue; Dentsply Tulsa Dental Specialties, Tulsa, OK], and ESX group [ESX; Brasseler USA, Savannah, GA]) of size 25 with a .04 taper and 25-mm length were tested in a metal block that simulated a canal curvature of 60° and a 5-mm radius curvature. The block was submerged in a water bath filled with water at 3°C, 22°C, 37°C, and 60°C. At each temperature, 30 files from each group were rotated at 500 rpm in the block. The number of cycles to fracture (NCF) was calculated. Statistical analysis was completed using a 1-way analysis of variance with significance at P < .05. ResultsVB group showed a significant decrease in NCF as the temperature increased from 3°C to 60°C. The ESX group showed a significant decrease in NCF as the temperature increased from 3°C to 37°C. The EF group showed a significant increase in NCF from 3°C to 22°C and a significant decrease in NCF from 22°C to 37°C. For each temperature, the EF group showed higher NCF than the VB group, which showed higher NCF than the ESX group. ConclusionsIn this in vitro study, temperature was found to significantly affect the cyclic fatigue of nickel-titanium rotary files. At each tested temperature, NCF was the highest for the EF group followed by the VB group and lowest for the ESX group. Future cyclic fatigue studies should be conducted at body temperature.

Comparative Analysis of Calcium Silicate–based Root Filling Materials Using an Open Apex Model

IntroductionMany new calcium silicate–based root filling materials have emerged in the market; however, their performance in the orthograde obturation of an open apex has not been evaluated. The purpose of this study was to compare the marginal adaptation of ProRoot MTA (Dentsply Tulsa Dental, Tulsa, OK), NeoMTA Plus (Avalon Biomed Inc, Bradenton, FL), and Endosequence BC RRM-Fast Set Putty (BC RRM-FS; Brasseler USA, Savannah, GA) after orthograde placement in roots with open apices. MethodsPalatal roots of maxillary molars were instrumented to create divergent open apices and divided into 4 groups for orthograde obturation: ProRoot MTA, NeoMTA Plus, BC RRM-FS, and BC RRM-FS + BC Sealer. Using a scanning electron microscope, the quality of material adaptation at the anatomic apex was evaluated by 5 blinded examiners; 3 mm of the root end was sectioned, and gap distance was measured at the material-dentin interface. Statistical analyses were performed using the Kruskal-Wallis test. ResultsThere were no significant differences in marginal adaptation among the 4 groups at the level of the anatomic apex (P = .175). BC RRM-FS + BC Sealer had a significantly smaller gap size after 3-mm root end resection compared with the other 3 groups (P < .01). No differences were observed among the other 3 materials. ConclusionsAll materials showed comparable marginal adaptation at the anatomic apex when used for orthograde obturation of open apices. Application of BC Sealer before the delivery of BC RRM-FS Putty enhanced the quality of adaptation coronal to the apex.

Dentinal Tubule Penetration of Tricalcium Silicate Sealers

IntroductionThe treatments for which mineral trioxide aggregate (MTA)-based materials can be used in dentistry are expanding. Smaller particle size and easier handling properties have allowed the advent of tricalcium silicate sealers including EndoSequence BC Sealer (Brasseler USA, Savannah, GA), QuickSet2 (Avalon Biomed, Bradenton, FL), NeoMTA Plus (Avalon Biomed), and MTA Fillapex (Angelus, Londrina, Brazil). The objective of this study was to measure the tubule penetration with these sealers using continuous wave (CW) and single-cone (SC) obturation techniques. MethodsEighty single-rooted teeth were randomly divided into 8 groups of 10 and obturated with 1 of the previously mentioned sealers mixed with trace amounts of rhodamine using either the CW or SC technique. Teeth were sectioned at 1 mm and 5 mm from the apex and examined under a confocal laser microscope. The percentage of sealer penetration and the maximum sealer penetration were measured. ResultsThe tricalcium silicate sealers penetrated tubules as deep as 2000 μm (2 mm). The percentage of sealer penetration was much higher 5 mm from the apex, with many specimens having 100% penetration for both SC and warm vertical techniques. MTA Fillapex, a resin-based sealer with less than 20% MTA particles, had significantly greater tubule penetration with a warm vertical technique versus the SC technique at the 1-mm level. ConclusionsWithin the limitations of this study, the CW and SC techniques produced similar tubule penetration at both the 1-mm and the 5-mm level with the tricalcium silicate sealers BC Sealer, QuickSet2, and NeoMTA Plus.

Bioactivity Potential of EndoSequence BC RRM Putty

IntroductionThe aim of this study was to characterize and assess the interaction of EndoSequence BC RRM putty (Brasseler USA, Savannah, GA) in contact with blood and simulated body fluid. Tricalcium silicate–based materials are in contact with blood and tissue fluids during and after their setting. These materials are hydraulic; thus, their properties improve in moist conditions. However, specific environmental conditions may modify the material setting. MethodsEndoSequence BC RRM putty was characterized by scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction analysis. This was done before setting and after contact with water, Hank's balanced salt solution, and heparinized whole blood. Furthermore, characterization of an explanted material from a failed root-end surgery was performed. ResultsThe EndoSequence BC RRM putty was composed of tricalcium silicate, tantalum oxide, and zirconium oxide. The tricalcium silicate reaction led to the formation of calcium hydroxide, and this was evident over the putty in contact with water and Hank's balanced salt solution. In the latter case, there was also the formation of globular crystals synonymous with hydroxyapatite formation. The material in contact with blood exhibited a poorly crystalline surface with additional peaks for calcium, phosphorus, and chlorine, whereas the material retrieved from the failed root-end surgery had deposition of calcium carbonate on its surface. ConclusionsThe environmental conditions affect the hydration of the EndoSequence RMM putty and consequentially the material interaction with the environment. However, in vitro material assessment may not be representative of the clinical situation because carbon dioxide present in vivo leads to the formation of calcium carbonate rather than the hydroxyapatite reported in in vitro studies.

A New Calcium Silicate–based Bioceramic Material Promotes Human Osteo- and Odontogenic Stem Cell Proliferation and Survival via the Extracellular Signal-regulated Kinase Signaling Pathway

IntroductionThe purpose of this study was to investigate odontogenic and osteogenic cell adhesion, proliferation, and survival on the surface of a newly developed bioceramic material (EndoSequence Root Repair Material [RRM]; Brasseler USA, Savannah, GA) and compare it with mineral trioxide aggregate (gray MTA) (ProRoot MTA; Dentsply Tulsa Dental, Tulsa, OK). A potential role of extracellular signal-regulated kinase (ERK) signaling in the RRM/MTA-induced cellular activities was also investigated. MethodsHuman bone marrow mesenchymal stem cells, periodontal ligament stem cells, and dental pulp stem cells were cultured on RRM- or MTA-coated slides. Cell proliferation was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays after 1, 3, and 5 days of growth. Cell survival was assessed under serum starvation (0.5% and 0.2% serum) using MTT assays. RRM and MTA surface characteristics and cell morphology were studied using a scanning electron microscope. The role of ERK signaling in RRM/MTA-induced cell proliferation/survival was studied using an ERK-specific inhibitor. ResultsAll cell types firmly attached to RRM- and MTA-coated plates. The coated surfaces had a granular appearance under the scanning electron microscope. Compared with those grown on uncoated plates, the cells on MTA/RRM-coated plates appeared healthy and smaller. Cell proliferation was significantly higher on RRM/MTA-coated surfaces (2- to 3-fold in cell number). The mitogenic effect on periodontal ligament stem cells and dental pulp stem cells was more pronounced with RRM than MTA (49% and 26% higher, respectively), but human bone marrow mesenchymal stem cells responded to both materials similarly. In serum-deprived conditions, significantly more cells (2- to 3-fold) survived on RRM/MTA surfaces. The cells grown on RRM/MTA surfaces showed sustained up-regulation of ERK phosphorylation, and blocking ERK signaling with U0126 significantly reduced RRM- and MTA-dependent cell survival. ConclusionsMTA and RRM are biocompatible and promote cell proliferation and survival in an ERK-dependent manner.

Surface microhardness of different thicknesses of a premixed bioceramic material with or without the application of a moist cotton pellet.

Background:This study was conducted to assess the effect of thickness and hydration condition on the surface microhardness of Endosequence Root Repair Material putty (ERRM; Brasseler USA, Savannah, GA), a premixed bioceramic material.Materials and Methods:Polymethyl methacrylate cylindrical molds with an internal diameter of 4 mm and three heights of 2, 4, and 6 mm were fabricated. In Group 1 (dry condition), the molds with heights of 2, 4, and 6 mm (10 molds of each) were filled with ERRM. In Groups 2 and 3 (wet condition), a distilled water- or phosphate-buffered saline (PBS)-moistened cotton pellet was placed directly on the upper surface of ERRM, respectively. The lower surface of ERRM was in contact with floral foams soaked with human blood. After 4 days, Vickers microhardness of the upper surface of ERRM was tested. The data were analyzed using two-way analysis of variance. Significance level was set at P < 0.05.Results:No significant difference was found between the microhardness of three thicknesses of ERRM (2, 4, and 6 mm) with or without placing a distilled water- or PBS-moistened cotton pellet over the material (P > 0.05).Conclusion:Based on the results of this study, it could be concluded that placing a moistened cotton pellet on ERRM putty up to 6 mm thick might be unnecessary to improve its surface microhardness and hydration characteristics.