White ProRoot Mineral Trioxide Aggregate Research Articles

Evaluation of the Marginal Adaptation of Two Hydraulic Calcium Silicate Cements Used in Apical Plugs: An In Vitro Study

Background: The emergence of new hydraulic calcium silicate cements has revolutionized endodontics, addressing the limitations of mineral trioxide aggregate (MTA). The aim of this study is to assess and compare the marginal adaptation of two calcium silicate-based cements (White ProRoot MTA® and TotalFill® BC RRM Fast Set PuttyTM), when creating apical plugs for teeth with open apices. Methods: twenty-four single-rooted teeth were divided into two groups—GMTA (plug with MTA®) and GTBC (plug with TotalFill® BC RRM Fast Set PuttyTM)—and were sectioned at 1 mm and 2 mm from the apex. The transverse sections were analyzed with scanning electron microscopy and the marginal adaptation of the cements was measured with ImageJ® 1.3 software. Statistical analysis (IBM® SPSS® statistics software version 27) was performed and statistical significance was set at 0.05 (p < 0.05). Results: There was a significant difference in the apical region, favoring White ProRoot MTA®, with a lower percentage of marginal adaptation failure (1.32 ± 4.47), presenting a statistically significant difference in the apical region (p = 0.029) but not in the cervical region of the apical plugs (p = 0.774). Conclusions: White ProRoot MTA® showed superior marginal adaptation in the apical section compared to TotalFill® BC RRM Fast Set PuttyTM.

Chemical and physical properties of radiopaque Portland cement formulation with reduced particle size.

This study compared the chemical and physical properties of an experimental radiopaque white Portland cement (REPC) with reduced particle size to ProRoot white mineral trioxide aggregate (WMTA). The particle size distribution of experimental Portland cement (EPC) was examined, and then nano-zirconium oxide (nano-ZrO) was added to produce REPC. Chemical analysis, initial setting time, pH values, and push-out bond strength were evaluated. Results showed that REPC had smallest particle size (354.5±26.45 nm), while PC had the largest (1,309.67±60.54 nm) (p<0.05). Differences in chemical composition were observed. REPC exhibited shorter setting time (32.7±0.58 min) compared to WMTA (131.67±2.89 min) and PC (163.33±2.89 min) (p<0.05). All groups showed alkaline pH (p<0.05). REPC demonstrated the highest push-out bond strength (22.24±4.33 MPa) compared with WMTA (15.53±3.26 MPa) and PC (16.8±5.43 MPa) (p<0.05). This cost-effective PC formulation reduced the setting time and increased the push-out bond strength while maintaining the alkaline properties of the original cements.

Effect of Intracoronal Sealing Biomaterials on the Histological Outcome of Endodontic Revitalisation in Immature Sheep Teeth—A Pilot Study

The influence of intracoronal sealing biomaterials on the newly formed regenerative tissue after endodontic revitalisation therapy remains unexplored. The objective of this study was to compare the gene expression profiles of two different tricalcium silicate-based biomaterials alongside the histological outcomes of endodontic revitalisation therapy in immature sheep teeth. The messenger RNA expression of TGF-β, BMP2, BGLAP, VEGFA, WNT5A, MMP1, TNF-α and SMAD6 was evaluated after 1 day with qRT-PCR. For evaluation of histological outcomes, revitalisation therapy was performed using Biodentine (n = 4) or ProRoot white mineral trioxide aggregate (WMTA) (n = 4) in immature sheep according to the European Society of Endodontology position statement. After 6 months' follow-up, one tooth in the Biodentine group was lost to avulsion. Histologically, extent of inflammation, presence or absence of tissue with cellularity and vascularity inside the pulp space, area of tissue with cellularity and vascularity, length of odontoblast lining attached to the dentinal wall, number and area of blood vessels and area of empty root canal space were measured by two independent investigators. All continuous data were subjected to statistical analysis using Wilcoxon matched-pairs signed rank test at a significance level of p < 0.05. Biodentine and ProRoot WMTA upregulated the genes responsible for odontoblast differentiation, mineralisation and angiogenesis. Biodentine induced the formation of a significantly larger area of neoformed tissue with cellularity, vascularity and increased length of odontoblast lining attached to the dentinal walls compared to ProRoot WMTA (p < 0.05), but future studies with larger sample size and adequate power as estimated by the results of this pilot study would confirm the effect of intracoronal sealing biomaterials on the histological outcome of endodontic revitalisation.

In Vivo Assessment of the Apatite-Forming Ability of New-Generation Hydraulic Calcium Silicate Cements Using a Rat Subcutaneous Implantation Model.

Hydroxyapatite formation on endodontic hydraulic calcium silicate cements (HCSCs) plays a significant role in sealing the root canal system and elevating the hard-tissue inductivity of the materials. This study evaluated the in vivo apatite-forming ability of 13 new-generation HCSCs using an original HCSC (white ProRoot MTA: PR) as a positive control. The HCSCs were loaded into polytetrafluoroethylene tubes and implanted in the subcutaneous tissue of 4-week-old male Wistar rats. At 28 days after implantation, hydroxyapatite formation on the HCSC implants was assessed with micro-Raman spectroscopy, surface ultrastructural and elemental characterization, and elemental mapping of the material-tissue interface. Seven new-generation HCSCs and PR had a Raman band for hydroxyapatite (v1 PO43- band at 960 cm-1) and hydroxyapatite-like calcium-phosphorus-rich spherical precipitates on the surfaces. The other six HCSCs with neither the hydroxyapatite Raman band nor hydroxyapatite-like spherical precipitates did not show calcium-phosphorus-rich hydroxyapatite-layer-like regions in the elemental mapping. These results indicated that 6 of the 13 new-generation HCSCs possessed little or no ability to produce hydroxyapatite in vivo, unlike PR. The weak in vivo apatite-forming ability of the six HCSCs may have a negative impact on their clinical performance.

Morphological and Chemical Analysis of Different Types of Calcium Silicate-Based Cements.

Objectives Particle size and shape can influence the properties of materials. However, to improve the physicochemical and biological properties of mineral trioxide aggregate (MTA), silicate-based hydraulic cements were introduced. This study aimed to evaluate and compare the major constituents and crystalline structures along with the surface morphology of different types of calcium silicate-based cement (CSC). Materials and Methods Six different types of CSC (white Portland cement, white ProRoot MTA, white MTA Angelus, Biodentine, and Endosequence, both putty and paste) were used in this study. Five samples of each material were analyzed in both uncured and cured cement using scanning electron microscopy/energy-dispersive X-ray (SEM/EDX), X-ray diffraction (XRD), and Fourier transform-infrared spectroscopy (FTIR). Results SEM analysis showed that the surfaces of all materials consisted of particle sizes ranging from 0.194 μm to approximately 51.82 μm. The basic elements found in both uncured and cured cement of all tested materials using EDX were carbon, calcium, silicon, and oxygen. A difference was observed in the presence or absence of magnesium, aluminum, bismuth, zirconium, and tantalum. XRD showed that all tested materials were composed mainly of tricalcium silicate and dicalcium silicate, which are the main components of Portland cement. FTIR analysis showed aromatic rings, phosphine PH, alkyl halides, and alcohol O-H groups in all tested materials but at different wavenumbers. Conclusions The different types of CSCs tested in this study were primarily modified types of Portland cement with the addition of radiopacifiers. ProRoot MTA and MTA Angelus contained bismuth oxide, Biodentine contains zirconium oxide, whereas Endosequence root repair materials (both putty and paste) contained zirconium oxide and tantalum oxide. Endosequence root repair materials showed smaller particle sizes than the other groups. White PC had the most irregular and large particle sizes. CSC had a smaller particle size, except for MTA Angelus. Clinical Relevance. The composition of CSC has a direct influence on the properties of these cements, which may affect the clinical outcome of the treatment.

Sealing ability of mineral trioxide aggregate, Biodentine, and EndoSequence RRM putty used as retrograde restorative material: An in vitro bacterial leakage model study

Sealing ability of mineral trioxide aggregate, Biodentine, and EndoSequence RRM putty used as retrograde restorative material: An in vitro bacterial leakage model study

Apical Sealing Ability of Two Calcium Silicate-Based Sealers Using a Radioactive Isotope Method: An In Vitro Apexification Model.

The aim of this study was to evaluate and compare the sealing ability of two calcium silicate-based sealers (TotalFill BC RRM Fast Set Putty and White ProRoot MTA) when used as apical plugs in immature teeth through nuclear medicine. Single-rooted extracted teeth (n = 34) had their crowns and root tip sectioned to obtain 14 mm long root segments to simulate an in vitro apexification model. Were created two experimental groups, namely MTA (n = 12) and BC (n = 12), and two control groups, PG (positive group, n = 5) and NG (negative group, n = 5). On the 4th day after placing the respective apical plug, the apical portions of the teeth were submerged in a solution of sodium pertechnetate (99mTcNaO4) for 3 h. Statistical analysis showed a significant difference between the MTA group and the controls (p < 0.05). The BC group had a significant difference regarding the negative control (p < 0.001) but showed no statistical significance regarding the positive control (p = 0.168). There was a statistically significant difference (p = 0.009) between the BC group (7335.8 ± 2755.5) and the MTA group (4059.1 ± 1231.1), where the last showed less infiltration. Within the limitations of this study, White ProRoot MTA had a significantly better sealing ability than TotalFill BC RRM Fast Set Putty.

Tissue response to white mineral aggregate-based cement containing barium sulfate as alternative radiopacifier: A randomized controlled animal study.

The purpose of this study was to investigate the tissue reaction stimulated by BaSO4 - and Bi2 O3 -containing White MTA Angelus, in comparison with Bi2 O3 -containing white Portland cement, and white ProRoot MTA. Thirty-six adult male Wistar rats (Rattus norvegicus), weighing between 250 and 300 g, were distributed into three groups (n = 12) in accordance with the period of sacrifice (15, 30, and 60 days). Four polyethylene tubes filled with the tested cements were implanted into the dorsum of each rat. Lateral wall of the tubes served as the negative control. After the experimental periods, the animals were euthanized by overdose of pentobarbital anesthetic solution, and the specimens were prepared for microscopic analysis under ×50, ×100, and ×400 magnifications. Inflammatory scores (0-3) were used to grade the tissue reaction. Data were analyzed by the Kruskal-Wallis test and Dunn's test for individual comparisons (p < .05). A mild to moderate inflammatory tissue reaction was observed at the 15-day period, which decreased over the course of the periods for all cements, except for Portland cement. There was no significant difference among the tissue responses for ProRoot MTA, BaSO4 - and Bi2 O3 -containing White MTA Angelus at the 60-day period (p > .05). The Portland group had moderate inflammatory reaction at the final period of analysis, which was statistically different when compared to the other groups (p < .05). The microscopic findings of this animal study suggest that the addition of BaSO4 to White MTA Angelus does not hampers the biocompatibility of the cement.

Accuracy of Conventional Periapical Radiography in Diagnosing Furcation Repair after Perforation Treatment

IntroductionPeriapical radiography (PR) is a diagnostic tool to be used by professionals in clinical practice. The method presents limitations, and doubts still exist about its value to evaluate furcation perforation and the reparative process of hard or soft tissues after treatment. Thus, the aim of this study was to evaluate the accuracy of PR as a diagnostic method to detect both resorption of the furcation area after induced experimental perforation and repair after perforation treatment using histopathological findings as a gold standard. MethodsThirty teeth of beagle dogs with furcation perforation were filled with Biodentine (Septodont, Saint-Maur-des-Fossés, France), ProRoot White mineral trioxide aggregate (Dentsply Tulsa Dental Specialties, Tulsa, OK), or gutta-percha and examined using PR and histology. Sensitivity, specificity, predictive values, and accuracy were calculated. ResultsPR detected repair and reabsorption of furcation perforation in 55% and 48% of the teeth, respectively. Histologic analysis showed furcation perforation in 66% and 21% of the teeth, respectively. Sensitivity and specificity of PR for the detection of repair were 0.84 and 1, respectively, whereas for resorption detection, the values were 0.43 and 0.65, respectively. Diagnostic accuracy for PR was 0.89 and 0.72 for repair and resorption of furcation perforation, respectively. PR showed more accurate diagnostic (true positives + true negatives/total) in repair detection compared with resorption of furcation perforation. ConclusionsWe conclude that PR is not adequate in detecting resorption progress after the treatment of furcation perforation, and we encourage the use of digital imaging when suspicious of a possible unsuccessful result after furcation perforation treatment.

Calcium Silicate-Based Cements as Root Canal Medicament.

PurposeThis study aims to retard the setting reaction of CSC by mixing it with 2% chlorhexidine gel (CHX) which will be used as an intracanal medicament, and to evaluate the removal of the experimental medicaments from the root canal.Materials and MethodsWhite Portland cement, white ProRoot MTA and Biodentine were mixed with 2% CHX. The setting time, flowability and film thickness of the CSC/CHX mixture (experimental medicaments) were assessed and measured following the standards of ISO specification. Calcium ion release was measured using ICP-OES, while pH was tested using a pH meter. Moreover, twenty single-rooted teeth were filled with the experimental medicaments for seven days, then the medicaments were removed and the samples analyzed using SEM. Calcium hydroxide paste was used as a control.ResultsThe setting time of the experimental medicaments was inhibited until 84 days. The calcium ion release of the experimental medicaments was significantly higher compared to the control over the period of 14 days (P<0.001). The mean pH value was above 11.45 for all tested materials over a period of 14 days, with no significant difference between them (P<0.05). There was no significant difference in film thickness of the experimental medicaments compared to the control (P> 0.05). However, the flowability of the experimental medicaments was significantly higher than the control (P<0.05). SEM showed no significant differences in the removal of the intracanal medicaments between all the tested groups.ConclusionThe addition of 2% CHX to CSCs retarded or inhibited its setting reaction over a period of 84 days. The calcium ion release and flowability of these experimental medicaments was found to be better than calcium hydroxide. Removal of the intracanal medicaments from the root canal was successfully achieved in all groups. Therefore, these experimental medicaments have the potential to be used as an enhanced root canal medicament.

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.

Immediate response of human dental pulp capped with mineral trioxide aggregate, Portland cement and biodentin

Background: The initial inflammatory reaction of pulp capping materials on the dental pulp has an intimate relation in promoting the future cellular differentiation and biomaterial mineralisation. So, analysis of immediate pulpal tissue reaction in vivo, is also important for evaluation of ultimate efficacy any pulp capping agent. To observe immediate inflammatory response of Human Dental Pulp capped with Mineral Trioxide Aggregate (MTA), Biodentin and Portland Cement (PC).&#x0D; Methods: A total of 70 permanent premolars teeth planned to be extracted for orthodontic alignment of occlusion were used as study sample. The teeth were divided into 3 experimental groups, MTA (n=20), Biodentin (n=20) Portland cement (n=20) and control group (n=10). After having an occlusal exposure of approximately 1.5 mm in diameter; in group A, pulp of teeth was capped with 2-mm-thick layer of ProRoot White MTA (Dentsply) and in group B, with sterile Biodentin (Septodont) according to the manufacturer’s recommendations. Whereas in group C, pulp of teeth was capped with sterile Portland Cement (PC). After placing the experimental material in each group, all teeth restored with glass i‹xiomer cement. After 24 hours the teeth were extracted, fixed in 10% buffered formalin solution, then decalcified by 10% nitric acid and embedded in paraffin. Finally, sectioned into 2 to 3-micron-thick serial sections in the linguo-buccal plane and stained with hematoxylin-eosin. After then the amount of pulp inflammation (type, intensity, and extension) were determined by using a predetermined evaluation criterion under an optical microscope at 40a magnification. Ten intact teeth, which received no exposure and pulp capping but extracted due to orthodontic purpose were also collected and treated as the control group (group D); undergone same histologic preparation and evaluation. Significantstatistical differences among the experimental groups were to be found (p&lt;0.05).&#x0D; Results: Histologically, all the three tested materials produced immediate pulpal tissue reaction. ‘Biodentin’ found to be most immediate pulpal tissue reactive (reactive in 100% cases) and ‘Portland Cement’ showed least immediate tissue reaction (only in 30.0% cases). whereas, MTA produced immediate tissue reaction only in 50.0% cases. Immediate pulpal inflammatory reaction in response to tested material found to be statistically significant different between ‘Biodentin’ and ‘Portland cmient’ (p=0.01), also between ‘Biodentin’ and ‘MTA’ and (p=0.001); but there was no statistically significant difference between ‘MTA’ and ‘Portland cement’ (p =0.197).&#x0D; Conclusion: Considering the maximum immediate pulpal tissue reaction (Inflammation), Biodentin is expected to produce most favorable ultimate bioactivity (biomaterial mineralization) after pulp capping.&#x0D; Bangladesh Med Res Counc Bull 2019; 45: 108-116

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.

The Effects of Three Bleaching Agents on Tooth Discoloration Caused by Mineral Trioxide Aggregate.

Successful outcome of pulp capping treatment using mineral trioxide aggregate (MTA), often leads to tooth discoloration. This study aimed to compare the efficacy of external bleaching technique with three bleaching agents naming hydrogen peroxide, carbamide peroxide and sodium perborate for correction of tooth discoloration caused by MTA. This in vitro, experimental study used 36 tooth blocks prepared from 12 bovine central incisors. White ProRoot MTA was applied in cavities; drilled in blocks for 40 days to cause discoloration. Then, the blocks were assigned to three experimental groups (n=12). Following application of hydrogen peroxide, carbamide peroxide and sodium perborate, the color parameters were determined at baseline and at 1, 7 and 14 days, using a spectrophotometer. Data were analyzed using repeated measure ANOVA and Tukey's test. No significant difference was noted in color change (∆E) immediately after bleaching with hydrogen peroxide and carbamide peroxide (P>0.05). However, these two groups had significant differences in ∆E with the sodium perborate group (P=0.001). Hydrogen peroxide group showed significantly higher ∆E at 1 week compared with other groups (P=0.01). The three groups were significantly different in ∆E at 2 weeks after bleaching (P=0.001). Pairwise comparisons revealed no significant difference between sodium perborate and carbamide peroxide in ∆E but they both had a significant difference with hydrogen peroxide (P=0.01). The three bleaching agents bleached the discoloured teeth effectively. Hydrogen peroxide had the highest efficacy whilst sodium perborate and carbamide peroxide had lower but similar efficacy.

In Vitro Mechanical Properties of Mineral Trioxide Aggregate in Moist and Dry Intracanal Environments.

Introduction:The purpose of this study was to examine the microhardness and modulus of elasticity (MOE) of White ProRoot MTA (Dentsply Tulsa Dental, Tulsa, OK) after setting in moist or dry intracanal conditions. Methods and Materials: To simulate root canal system, 14 polyethylen molds with internal diameter of 1 mm and height of 12 mm were used. These molds were filled with 9-mm thick layers of White ProRoot Mineral Trioxide Aggregate (MTA; Dentsply Tulsa Dental, Tulsa, OK). The experimental group (n=7) had a damp cotton pellet with 1.5 mm height and a 1.5 mm layer of resin composite placed on it. In control group (n=7) the whole 3 mm above MTA were filled with resin composite. The specimens were kept in 37°C and relative humidity of 80% for 4 days in order to simulate physiological conditions. Specimens were longitudinally sectioned and nanoindentation tests were carried out using Berkovich indenter at loading rate of 2 mN/s at 4×5 matrices of indents which were located in the coronal, middle and apical thirds of the specimen’s cross section, to evaluate the microhardness and modulus of elasticity of the specimen to appraise the progression of the setting process. Differences were assessed using nonparametric generalized Friedman rank sum and Wilcoxon Rank-Sum tests. Results:Statistical analysis showed that there was a significant difference in microhardness and MOE between control and experimental groups at coronal (P<0.001), middle (P<0.001) and apical (P<0.001) thirds of the simulated rod from simulated apical foramen. Kruskal-Wallis test showed no significant effect of depth on microhardness of material in experimental or control groups. Conclusion: Within limitations of this in vitro study, it seems that moist intracanal environment improves setting of MTA in various depths.

The effect of accelerated mineral trioxide aggregate on odontoblastic differentiation in dental pulp stem cell niches.

To investigate the effect of accelerated-set mineral trioxide aggregate (MTA) on the proliferation and odontoblastic differentiation of human dental pulp cell niches (DPSC). ProRoot White MTA (WMTA; Dentsply Tulsa Dental, Johnson City, TN, USA) was mixed with various additives, which included distilled water, 2.5% disodium hydrogen phosphate (Na2 HPO4 ; Merck, Darmstadt, Germany) and 5% calcium chloride (CaCl2 ; Merck). DPSC niches extracted from third molars were cultured directly on MTA in the culture medium. Cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4- sulphophenyl)-2H-tetrazolium (MTS) assay. Cell growth and expression of odontoblastic differentiation markers (dentine sialophosphoprotein (DSPP) and collagen type 1 (COL1)) were determined using Real-Time Polymerase Chain Reaction analysis. Osteo-/odontogenic differentiation of DPSC niches was evaluated by measurement of alkaline phosphatase activity (ALP). Calcium deposition was assessed using von Kossa staining. The results were analysed statistically using Mann-Whitney tests and Kruskal-Wallis tests. MTA mixed with 5% CaCl2 and 2.5% Na2 HPO4 exhibited optimal cell viability (P<0.05) compared to MTA mixed with distilled water. MTA mixed with 5% CaCl2 and 2.5% Na2 HPO4 significantly increased ALP activity (P<0.05), significantly promoted mineralization nodule formation (P<0.05) and significantly enhanced the mRNA expression level of the osteogenic/odontogenic markers (P<0.05; DSPP and COL1) compared with MTA mixed with distilled water. MTA mixed with 5% CaCl2 and 2.5% Na2 HPO4 was biocompatible with dental pulp stem cell niches. Accelerated-set MTA promoted better differentiation in DPSC niches than conventional MTA. The accelerators could provide an alternative to MTA mixed with distilled water.

Evaluation of the Ca ion release, pH and surface apatite formation of a prototype tricalcium silicate cement.

To evaluate the Ca2+ -releasing, alkalizing and apatite-like surface precipitate-forming abilities of a prototype tricalcium silicate cement, which was mainly composed of synthetically prepared tricalcium silicate and zirconium oxide radiopacifier. The prototype tricalcium silicate cement, white ProRoot MTA (WMTA) and TheraCal LC (a light-cured resin-modified calcium silicate-filled material) were examined. The chemical compositions were analysed with a wavelength-dispersive X-ray spectroscopy electron probe microanalyser with an image observation function (SEM-EPMA). The pH and Ca2+ concentrations of water in which the set materials had been immersed were measured, and the latter was assessed with the EDTA titration method. The surface precipitates formed on the materials immersed in phosphate-buffered saline (PBS) were analysed with SEM-EPMA and X-ray diffraction (XRD). Kruskal-Wallis tests followed by Mann-Whitney U-test with Bonferroni correction were used for statistical analysis (α=0.05). The prototype cement contained Ca, Si and Zr as major elemental constituents, whereas it did not contain some metal elements that were detected in the other materials. The Ca2+ concentrations and pH of the immersion water samples exhibited the following order: WMTA=prototype cement>TheraCal LC (P<0.05). All three materials produced Ca- and P-containing surface precipitates after PBS immersion, and the precipitates produced by TheraCal LC displayed lower Ca/P ratios than those formed by the other materials. XRD peaks corresponding to hydroxyapatite were detected in the precipitates produced by the prototype cement and WMTA. The prototype tricalcium silicate cement exhibited similar Ca2+ -releasing, alkalizing and apatite-like precipitate-forming abilities to WMTA. The Ca2+ -releasing, alkalizing and apatite-like precipitate-forming abilities of TheraCal LC were lower than those of the other materials.

Effect of Sodium Hypochlorite on Push-out Bond Strength of Four Calcium Silicate-based Endodontic Materials when used for repairing Perforations on Human Dentin: An in vitro Evaluation.

This study aimed to evaluate the push-out bond strength of NeoMTA Plus (NMTA), EndoSequence root repair material fast set putty (ERRMF), biodentine (BD), and ProRoot white mineral trioxide aggregate (PMTA) when used as perforation repair materials after exposure to 2.5% sodium hypochlorite (NaOCl) during the early setting phase. Horizontal midroot sections were prepared from single-rooted human teeth. Sections (n = 144) were randomly divided into four groups: PMTA, BD, NMTA, and ERRMF. Materials were condensed and allowed to set for 10 minutes. The groups were further divided into two subgroups. The NaOCl group included specimens that were immersed in 2.5% NaOCl for 30 minutes, and the control group included specimens on which a wet cotton pellet was placed over the test material. After 48 hours, the highest force applied to the materials at the time of dislodgement was recorded. Slices were then examined under a digital microscope to evaluate the nature of the bond failure. The surfaces of two specimens from each subgroup were observed by scanning electron microscopy. Data were statistically analyzed with two-way and one-way analysis of variances, independent t-tests, and chi-square tests. The statistical significance was set at 0.05. In NaOCl-treated groups, PMTA showed a significantly higher push-out bond strength than the other three materials (p = 0.00). In the control groups, the bond strength of BD was significantly higher than that of PMTA, ERRMF, and NMTA (p < 0.05). Compared with the control group, NaOCl treatment significantly increased the push-out bond strength of PMTA (p = 0.00) and ERRMF (p = 0.00) and significantly reduced the bond strength of BD (p = 0.00) and NMTA (p = 0.03). None of the specimens showed an adhesive type of failure. The majority of the samples exhibited a cohesive failure type. Morphological observations revealed that the surfaces exhibited cubic crystals. In ERRMF, the crystals were few in number. Sodium hypochlorite enhanced the crystallization of NMTA. The push-out bond strengths of PMTA and ERRMF were significantly increased after exposure to 2.5% NaOCl in the early setting phase, and those of BD and NMTA were significantly decreased. The results of the present study suggest that early exposure of NaOCl increase the push-out bond strength of PMTA and ERRMF. PMTA had the highest push-out values. Therefore, it would be a potentially useful perforation repair material for single visit endodontic treatment.

Effect of Blood Exposure on Push-Out Bond Strength of Four Calcium Silicate Based Cements.

Introduction:The purpose of this study was to compare the push-out bond strength of white ProRoot Mineral Trioxide Aggregate (MTA), Biodentine, calcium-enriched mixture (CEM) cement and Endosequence Root Repair Material (ERRM) putty after exposure to blood. Methods and Materials:A total of 96 root dentin slices with a standardized thickness of 1.00±0.05 mm and standardized canal spaces were randomly divided into 4 main experimental groups (n=24) according to the calcium silicate based cement (CSC) used: white ProRoot MTA, CEM Cement, ERRM Putty and Biodentine. Specimens were exposed to whole fresh human blood and then subdivided into two subgroups depending on the exposure time (24 or 72 h). Push-out bond strength was measured using a universal testing machine. Failure modes were examined under a light microscope under ×10 magnification. Data were analyzed using the two-way ANOVA test. Results:Biodentine exhibited the highest values regardless of the exposure time. The lowest push-out strength values were seen in white ProRoot MTA and CEM cement in both post exposure times. After exposure to blood, the push-out bond strength of all materials increased over time. This increase was only statistically significant in white ProRoot MTA and ERRM specimens. The dominant failure mode in all CSCs was the adhesive mode. Conclusion:Biodentine showed the highest values of push-out bond strength and may be better options for situations encountering higher dislocation forces in a short time after cement application.

Superfast Set, Strong and Less Degradable Mineral Trioxide Aggregate Cement.

Purpose Despite the good sealing ability and biocompatibility of mineral trioxide aggregate (MTA), its slow setting, high degradation, and weakness limit its use in surgical endodontics and high stress-bearing areas. This study aimed to develop two new liquids to control these drawbacks. They were prepared from calcium chloride, fumed silica, and hydroxyapatite or calcium phosphate and coded “H” and “P,” respectively. Methods Portland cement, Grey ProRoot® MTA, and white ProRoot MTA were mixed with distilled water (control) or liquid “H” or “P.” The pH, setting time, degradation rate, leachant/precipitate' composition, compressive strength, and morphology were assessed. Results Both liquids maintained MTA's high alkalinity and reduced the setting time by 1-2 orders of magnitude. Both liquids, H in particular, significantly reduced the degradation rate of Grey ProRoot and White ProRoot MTA®. Calcite has been identified as the main phase of the leachant or precipitate formed during the cement's degradation. Calcium hydroxide or hydroxyapatite was also identified with Grey ProRoot MTA mixed with H liquid. These liquids also significantly increased the compressive strength with no statistical differences between them; this was associated with the production of dense, consolidated structures. Conclusions The modified MTA could be used in surgical endodontics and high stress-bearing areas.