Physicochemical,biological, and antibacterial evaluation of tricalcium silicate-based reparative cements with different radiopacifiers

ObjectiveTo evaluate tricalcium silicate-based (TCS) experimental materials, associated with zirconium oxide (ZrO₂), calcium tungstate (CaWO₄) or niobium oxide (Nb₂O₅) radiopacifiers, in comparison with MTA Repair HP (Angelus).MethodsPhysicochemical tests: setting time, radiopacity, pH and solubility. In vitro assays: cytotoxicity: MTT and Neutral Red – NR; cell bioactivity: alkaline phosphatase activity (ALP), Alzarin red staining (ARS) and real time PCR (qPCR). Antibacterial activity: direct contact on Enterococcus faecalis in the planktonic form. Physicochemical and ARS data were submitted to ANOVA/Tukey tests; antibacterial activity, to Kruskall–Wallis and Dunn tests; MTT, NR, ALP and qPCR were analyzed by ANOVA/Bonferroni tests (α = 0.05).ResultsTCS + CaWO₄ presented the longest setting time and MTA HP the shortest. Except for TCS, all the materials presented radiopacity above 3 mmAl. The cements had alkaline pH, antibacterial activity, low solubility and no cytotoxic effects. The highest ALP activity occurred in 14 days, especially to TCS, TCS + ZrO₂ and TCS + CaWO₄. TCS + ZrO₂, TCS + Nb₂O₅ and MTAHP had higher mineralized nodule formation than those of the negative control (NC). After 7 days, there was no difference in mRNA expression for ALP, when compared to NC. However, after 14 days there was no overexpressed ALP mRNA, especially TCS + Nb₂O₅, in relation to the CN. All the materials presented antimicrobial action.SignificanceThe pure tricalcium silicate associated with ZrO₂, CaWO₄ or Nb₂O₅ had appropriate physicochemical properties, antibacterial activity, cytocompatibility and induced mineralization in Saos-2, indicating their use as reparative materials.     

The effect of bleaching agents on the compressive strength of calcium silicate‐based materials

The present study aimed to evaluate the effect of sodium perborate on the compressive strength of calcium silicate‐based materials. ProRoot wMTA, MTA Plus, NeoMTA Plus and Biodentine discs with 5 mm thickness and 4 mm diameter were prepared. Thirty discs from each material were used for compressive strength testing and divided into two groups: control and bleaching (n = 15). The sodium perborate was mixed with 30% hydrogen peroxide in a creamy consistency and placed on the surface of the specimens. Specimens were tested in an Instron machine, and compressive strength values were recorded and compared. The data were analysed using one‐way anova and post hoc Tukey tests. Compressive strength of all tested materials significantly decreased after bleaching (P < 0.05). SEM examination revealed deterioration on materials’ surfaces after bleaching. Application of sodium perborate and hydrogen peroxide reduced the compressive strength of ProRoot wMTA, MTA Plus, NeoMTA Plus and Biodentine.     

Antibacterial,biological, and physicochemical properties of root canal sealers containing chlorhexidine-hexametaphosphate nanoparticles

ObjectiveThe aim of this study was to evaluate the influence of the incorporation of chlorhexidine-hexametaphosphate nanoparticles (CHX-HMP NPs) on antibacterial, cytotoxic and physicochemical properties of AH Plus (AH), MTA Fillapex (MTA) and Pulp Canal Sealer (PCS).MethodsThe NPs were synthesized and characterized by Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), zeta potential, Atomic Force Microscopy (AFM) and Energy-Dispersive X-ray Spectroscopy (EDS). The incorporation was made by weight, 2% and 5% of NPs. The antimicrobial activity, cytotoxicity, flow, radiopacity, setting time, solubility and pH were evaluated. The statistical analysis was performed by two-way analysis of variance test and Tukey post hoc test (P < 0.05).ResultsSEM analysis showed the tendency for CHX-HMP NPs to cluster, the effective mean diameter measured by DLS: 169.39 nm and the zeta potential: -10.18 mV. The NPs were individually measured by AFM: 22.99–52.75 nm. EDS analysis identified the presence of C, N, O, Na, P, Cl. After incorporation: The Direct Contact Test showed an increase in the antimicrobial action of AH, PCS and MTA; the sealers showed a decrease in flow and at 24 h of immersion also an increase in solubility, but did not affect the radiopacity of the samples; AH setting time increased and MTA did not reach setting under any of the conditions tested. All samples showed a decrease in pH value as the immersion time progressed.SignificanceThe incorporation of NPs can improve the antimicrobial performance of endodontic sealers without impairing other biological and physicochemical properties.     

Antibacterial activity of endosequence root repair material and proroot MTA against clinical isolates of Enterococcus faecalis

Introduction

Endodontic repair materials such as mineral trioxide aggregate (MTA) are used for various endodontic procedures. An alternative material to MTA with purportedly improved handling properties is EndoSequence Root Repair Material, which is available as premixed putty (ESP) or syringeable paste (ESS) and is described as possessing antibacterial activity during its setting reaction due to its highly alkaline pH. The aim of this in vitro study was to determine whether ESP and ESS possess antibacterial properties against a collection of Enterococcus faecalis strains recovered from root canal infections. The hypotheses tested were that (1) ESP and ESS possess antibacterial activity during their setting reaction, (2) there is no difference between ESP, ESS, and MTA in antibacterial activity, and (3) E. faecalis strains isolated from root canals differ in susceptibility to the materials.

Methods

The direct contact test was used. ESP, ESS, and white MTA were preincubated at 37°C in >95% humidity for 30 minutes and 24 hours before 1-hour direct contact exposure to E. faecalis strains (n = 10). Absence of antibacterial carryover effect from the materials to the bacterial cultures was confirmed. Log₁₀ viable counts were compared by using analysis of variance with significance level at P ≤ .05.

Results

Combining data for all strains, the mean (± standard deviation) log₁₀ viable counts for ESP (4.55 ± 0.85), ESS (4.5 ± 0.95), and MTA (4.12 ± 1.26) were significantly lower than for untreated controls (7.40 ± 0.33) (P < .0001). The reduction in viable counts ranged from 1.86 ± 0.24 to 4.78 ± 0.42, with no statistically significant differences between the materials or preincubation periods. One strain was significantly more susceptible than 4 other strains.

Conclusions

ESP, ESS, and MTA had similar antibacterial efficacy against clinical strains of E. faecalis. Clinical strains varied in their susceptibility to the root repair materials.     

Association between Intracanal Medicament Radiopacity and Streak Artifact Production Using Cone-beam Computed Tomography: A Laboratory Study

IntroductionThis study aimed to calculate the correlation between the radiopacity levels of various intracanal medicaments and radiolucent streak formation using cone-beam computed tomography (CBCT).MethodsSeven commercially-available intracanal medicaments were tested, which contained different amounts of radiopacifier [Consepsis, Ca(OH)₂, UltraCal XS, Calmix, Odontopaste, Odontocide, and Diapex Plus]. Their radiopacity levels were measured according to the International Organization for Standardization 13116 testing standards (mmAl). Subsequently, the medicaments were placed in 3 canals of radiopaque artificial printed maxillary molars (n = 15 roots per medicament), leaving the second mesiobuccal canal empty. CBCT imaging was carried out using an Orthophos SL 3-dimensional scanner under recommended manufacturer exposure settings. Radiopaque streak formation was assessed by a calibrated examiner using a previously published grading system (0–3). The Kruskal-Wallis and Mann-Whitney U tests with and without Bonferroni correction were used to compare radiopacity levels and radiopaque streak scores for the medicaments. Their relationship was assessed using the Pearson correlation coefficient. The level of significance was set as (α = 0.05).ResultsDiapex plus presented with the highest radiopacity levels (4.98 ± 0.01) and radiopaque streak scores [middle third (2.8 ± 0.18); apical third (2.73 ± 0.43)]; which was similar to UltraCal XS's radiopaque streak scores [middle third (2.8 ± 0.92); apical third (2.73 ± 0.77)]. Consepsis had the lowest radiopacity levels (0.12 ± 0.05), followed by Odontocide (0.60 ± 0.05). Consepsis and Ca(OH)₂ were scored 0 for artifacts in all roots at all levels. A high positive correlation (R = 0.95) was found between radiopacity and streak formation.ConclusionsThe radiopacity of intracanal medicaments varies and strongly correlates with the formation of radiolucent streak artifacts during CBCT.     

Quaternary ammonium compound as antimicrobial agent in resin-based sealants

Objectives

The aim of this study was to evaluate the influence of [2-(methacryloyloxy)ethyl] trimethylammonium chloride (METAC) in the physico-chemical properties, antibacterial activity and cytotoxicity of an experimental resin–based sealant.

Materials and methods

An experimental resin-based sealant was formulated with dimethacrylates and a photoinitiator system. METAC was added at 2.5 wt.% (G_2.5%) and 5 wt.% (G_5%) into the experimental resin–based sealant, and one group remained without METAC as control (G_CTRL). The resin-based sealants were analysed for polymerization behaviour and degree of conversion (DC), Knoop hardness (KHN) and softening in solvent (ΔKHN), ultimate tensile strength (UTS), contact angle, surface free energy (SFE), immediate and long-term micro-shear bond strength (μ-SBS) and antibacterial activity and cytotoxicity against human keratinocytes.

Results

The experimental resin–based sealants presented different polymerization behaviours without significant differences in the DC (p > 0.05). There was no significant difference for initial KHN (p > 0.05). The ΔKHN ranged from 51.62 (±3.70)% to 62.40 (±4.14)%, with higher values for G_5% (p < 0.05). G_2.5% and G_5% had decreased μ-SBS between immediate and long-term tests (p < 0.05) without significant differences among groups in the immediate and long-term analyses (p > 0.05). There were no significant differences for UTS, contact angle and SFE among groups (p > 0.05). G_2.5% and G_5% presented immediate and long-term antibacterial activity (p < 0.05) without cytotoxicity compared to G_CTRL (p > 0.05).

Conclusion

The addition of METAC provided antibacterial activity to the experimental resin–based sealant.

Clinical relevance

METAC is an effective quaternary ammonium compound as an antibacterial agent for resin-based sealants without cytotoxic effects against human keratinocytes.

     

Novel antibacterial dental resin containing silanized hydroxyapatite nanofibers with remineralization capability

ObjectivesSecondary caries is the primary issue that causes restoration failure. The objectives of this study were to: (1) synthesize silanized hydroxyapatite nanofibers loaded with erythromycin (s-HAFs@EM); (2) evaluate the mechanical property, antibacterial activity, and remineralization capability of the novel dental resin containing s-HAFs@EM.Methodss-HAFs were prepared by the solvothermal approach and loaded with EM. Characterization and antibacterial activity were evaluated. Subsequently, s-HAFs@EM were incorporated into dental resin at different mass fractions (5 %, 10 %, 15 %, and 20 %), and then they were submitted to characterization, including mechanical property, antibacterial activity, remineralization capability, and cytotoxicity.Resultss-HAFs@EM were successfully synthesized, and they exhibited excellent antibacterial activity. Resin containing 15 % s-HAFs@EM exhibited the best flexural strength (118.67 ± 15.71 MPa) and elastic modulus (2.02 ± 0.30 GPa) (P < 0.05), which were increased by 65.43 % and 90.7 %, compared to those of neat resin, respectively. Resin with 15–20 % s-HAFs@EM showed high antibacterial rate (>85 %) when compared control group (P < 0.05). Furthermore, resin also exhibited a definite remineralization capability and good biosafety in vitro.SignificanceThis novel multifunctional resin with improved mechanical property, desirable antibacterial activity and remineralization capability is promising to combat secondary caries.     

Influence of composition on setting kinetics of new injectable and/or fast setting tricalcium silicate cements

ObjectivesNew commercial tricalcium silicate based cements were elaborated to improve handling properties and setting time. The goals of the present work were: (i) to determine the composition of the new injectable and/or fast setting calcium silicate based cements, and (ii) to investigate the impact of the differences in composition on their setting kinetics.MethodsThe materials considered were Angelus MTA™, Biodentine™, MM-MTA™, MTA-Caps™, and ProRoot MTA™ as control.Elemental composition of materials was studied by Inductively Coupled Plasma-Atomic Emission Spectroscopy and X-ray Energy Dispersive analysis, whereas phases in presence were analyzed by Micro-Raman spectroscopy and X-ray Diffraction analysis and cement surface by Scanning Electron Microscope. Setting kinetics was evaluated using rheometry.ResultsElemental analysis revealed, for all cements, the presence of three major components: calcium, silicon and oxygen. Chlorine was detected in MM-MTA, MTA-Caps and Biodentine. Different radio-opacifiers were identified: bismuth oxide in ProRoot MTA, Angelus MTA and MM-MTA, zirconium oxide in Biodentine and calcium tungstate (CaWO₄) in MTA-Caps. All cements were composed of di- and tri-calcium silicate, except Biodentine for which only the latter was detected. Major differences in setting kinetics were observed: a modulus of 8 × 10⁸ Pa is reached after 12 min for Biodentine, 150 min for MM-MTA, 230 min for Angelus MTA and 320 min for ProRoot MTA. The maximum modulus reached by MTA-Caps was 7 × 10⁸ Pa after 150 min.SignificanceEven if these cements possess some common compounds, major differences in their composition were observed between them, which directly influence their setting kinetics.     

Analysis of radiopacity,pH and cytotoxicity of a new bioceramic material

Objective

RetroMTA^® is a new hydraulic bioceramic indicated for pulp capping, perforations or root resorption repair, apexification and apical surgery. The aim of this study was to compare the radiopacity, pH variation and cytotoxicity of this material to ProRoot^® MTA.

Material and Methods

Mixed cements were exposed to a digital x-ray along with an aluminum stepwedge for the radiopacity assay. pH values were verified after incubation period of 3, 24, 48, 72 and 168 hours. The cytotoxicity of each cement was tested on human periodontal ligament fibroblasts using a multiparametric assay. Data analysis was performed using ANOVA and Tukey’s post hoc in GraphPad Prism.

Results

ProRoot^® MTA had higher radiopacity than RetroMTA^® (p<0.001). No significant differences were observed for the pH of the materials throughout experimental periods (p>0.05) although pH levels of both materials reduced over time. Both ProRoot^® MTA and RetroMTA^® allowed for significantly higher cell viability when compared with the positive control (p<0.001). No statistical difference was observed between ProRoot^® MTA and RetroMTA^® cytotoxicity level in all test parameters, except for the ProRoot^® MTA 48-hour extract media in the NR assay (p<0.05).

Conclusion

The current study provides new data about the physicochemical and biological properties of Retro^® MTA concerning radiopacity, pH and cytotoxic effects on human periodontal ligaments cells. Based on our findings, RetroMTA^® meets the radiopacity requirements standardized by ANSI/ADA number 57², and similar pH values and biocompatibility to ProRoot^® MTA. Further studies should be performed to evaluate additional properties of this new material.     

Radio-opaque polyethylene for personalized craniomaxillofacial implants

Objective

This study aimed to present a new possibility to create radio-opaque implant material for craniomaxillofacial reconstruction.

Materials and methods

The test disks made of the own compound of polyethylenes with addiction of 2, 4, and 6 % of weight TiO₂ was investigated for cytotoxicity [each group 15 disks respectively]. Next, computed tomography of the disks was performed in environment of muscle and fat. Hardness, tensile modulus and strength, and compressive modulus and strength were tested too.

Results

Deterioration of mechanical properties of the composites containing titanium dioxide was observed [hardness, tensile modulus and strength, compressive modulus and strength, respectively: 56.7 ± 1.6 shore D, 354 ± 52, 22.5 ± 1.3, 21.8 ± 1.1, and 2995 ± 327 MPa as addiction of 2 % TiO₂; 52.0 ± 0.9 shore D, 347 ± 66, 18.0 ± 0.7, 14.2 ± 0.9, and 1396 ± 477 MPa as 4 % TiO₂; 51.3 ± 1.3 shore D, 316 ± 9, 17.4 ± 0.2, 13.6 ± 0.6, and 1100 ± 144 MPa as 6 % TiO₂ added]. The test disks revealed no cytotoxicity effect on human osteoblasts. The new material presents mild radio-opacity which was enough to observe the implant in relation to fat and muscle, but with no visible effect of beam hardening.

Conclusion

In view of the performed tests, the polyethylene enriched by titanium dioxide seems to be a proper material to consider manufacturing of craniomaxillofacial implants.

Clinical relevance

Maxilloafacial surgery is still looking for new implantologic materials. The proposed one is a new way to manufacture an implant visible in computed tomography which does not interfere with its shape in radiological examination and makes it possible to observe the surrounding soft tissues.

     

Controlled drug delivery from metronidazole-containing bioactive endodontic cements

ObjectivesThis study aims to formulate metronidazole liquid nanocapsules (MTZ_LNC) and evaluate their effect on the physicochemical and biological properties of calcium silicate-based bioactive endodontic cements, in vitro.MethodsA MTZ_LNC suspension was formulated by deposition of the preformed polymer and characterized by laser diffraction and high-performance liquid chromatography (HPLC). Calcium silicate (CS) was mixed with a radiopaque agent (calcium tungstate - CaWO₄), at 10 wt%, to produce the cement powder. Cements liquids were used with two concentrations of MTZ_LNC suspension: 0.3 mg/ml and 0.15 mg/ml. Cements prepared with distilled water were used as the control. The radiopacity, setting time, and flow were evaluated following ISO 6876:2012. The compressive strength analysis was conducted according to ISO 9917:2007. pH and mineral deposition were evaluated after immersion in simulated body fluid (SBF). Cell behavior was evaluated by the viability of pre-osteoblastic cells and pulp fibroblasts by SRB and MTT and the antibacterial activity against Enterococcus faecalis was analyzed immediately and after nine months of water storage.ResultsMTZ_LNCs were formulated with a median diameter of 148 nm and 83.44 % load efficiency. Increased flow and reduced strength were observed for both MTZ_LNCs concentrations. The incorporation of MTZ_LNCs maintained the ability of cements to increase pH media and promote mineral deposition over the samples, without promoting cytotoxicity. A 2 log₁₀ reduction in E. faecalis CFU was observed immediately and after nine months in water storage.ConclusionThe formulation of MTZ_LNCs allowed the development of antibacterial calcium silicate-based-cements with suitable physicochemical properties and bioactivity, with a reduction in mechanical strength. The 0.3 mg/ml concentration in cements liquid promoted effective and sustainable antibacterial activity.     

The influence of different radiopacifying agents on the radiopacity,compressive strength,setting time,and porosity of Portland cement

Objectives

The aims of this study were to evaluate the radiopacity, compressive strength, setting time, and porosity of white Portland cement (PC) with the addition of bismuth oxide (Bi₂O₃), zirconium dioxide (ZrO₂), and ytterbium trifluoride (YbF₃) after immersion at 37 °C for 7 days in distilled water or phosphate buffer saline.

Materials and methods

Specimens measuring 8 mm in diameter and 1 mm in thickness were fabricated from PC with the addition of 10, 20, and 30 wt% Bi₂O_3, ZrO₂ or YbF₃. ProRoot MTA (Dentsply, Tulsa, OK, USA) and pure PC were used as controls. For radiopacity assessments, specimens were radiographed alongside a tooth slices and an aluminum stepwedge on Extraspeed occlusal dental films (Insight Kodak, Rochester, New York). Mean optical density of each specimen was calculated and used to express radiopacity of the material as an equivalent thickness of aluminum. Compressive strength was measured by using 4-mm diameter and 6-mm high specimens and Universal testing machine. High-pressure mercury intrusion porosimeter (Carlo Erba Porosimeter 2000) was employed to measure the porosity of the specimens. The setting time was measured by using a needle of 100 g in weight. The morphology of specimens was evaluated using a scanning electron microscope (TESCAN Mira3 XMU, USA Inc.). Data were analyzed by one-way ANOVA and post hoc Tukey test (P?<?0.05).

Results

The PC with the addition of at least 10 wt% Bi₂O₃ and 20 wt% ZrO₂ or YbF₃ demonstrated greater radiopacity value than the recommended 3 mmAl cut-off. ZrO₂ and YbF₃ increased the compressive strength of PC, but it was not statistically significant (P?>?0.05), while Bi₂O₃ decreased it (P?<?0.05). All radiopacifiers significantly increased the porosity of the experimental cements (P?<?0.05). Bi₂O₃ extended the setting time of PC (P?<?0.05), whilst ZrO₂ and YbF₃ did not significantly affect it (P?>?0.05).

Conclusions

ZrO₂ and YbF₃ may be used as a suitable alternative to replace Bi₂O₃ in MTA without influencing its physical properties.     

Antibacterial activity improvement of dental glass-ceramic by incorporation of AgVO3 nanoparticles

ObjectiveThis study aimed to investigate the role of the incorporation of an antibacterial nanoceramic (AgVO₃) on the properties of a restorative dental glass-ceramic.MethodA commercially available restorative glass-ceramic, commonly designated as porcelain (IPS d.SIGN) was functionalized with an antibacterial agent (nanostructured β-AgVO₃), synthesized by a hydrothermal route. Both functionalized and pristine samples were processed according to the manufacturer's instructions. All samples were characterized by X-ray diffraction, Rietveld refinement, particle size distribution, Scanning Electron Microscopy, chemical solubility, and Inductively Coupled Plasma Spectroscopy. Their antibacterial potential (Mueller-Hinton test) was analyzed against gram-positive (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli).ResultsThe commercial glass-ceramic showed leucite (KAlSi₂O₆) as the only detectable crystalline phase, and, for both strains, no antibacterial activity could be detected in the Mueller-Hinton agar plates test. A monophasic, needle-shaped, and nanometric β-AgVO₃ powder was successfully synthesized by a simple hydrothermal route. After thermal treatment, glass-ceramic samples containing different percentages of β-AgVO₃ showed a second crystalline phase of microline [K_0.95(AlSi₃O₈)]. For modified samples, inhibition halos were easily visible on the Mueller-Hinton test, which ranged from 11.1 ± 0.5 mm to 16.6 ± 0.5 mm and 12.7 ± 0.3 mm to 15.5 ± 0.3 mm in the S. aureus and E.coli cultures, respectively, showing that the halos formed were dose-dependent. Also, increasing the percentage of β-AgVO₃ promoted a significant increase in chemical solubility, from 72 µg/cm² (samples with 1 wt% of β-AgVO₃) to 136 µg/cm² (samples with 2 wt% of β-AgVO₃), which was associated with the silver and vanadium ions released from the glass matrix.Significance:Our in vitro results indicate that IPS d.SIGN, as most of the dental glass-ceramics, do not exhibit antibacterial activity per se. Nonetheless, in this concept test, we demonstrated that it is possible to modify dental veneering materials giving them antibacterial properties by adding at least 2 wt% of β-AgVO₃, a nanomaterial easily synthesized by a simple route.     

The effect of various concentrations of iodine potassium iodide on the antimicrobial properties of mineral trioxide aggregate – a pilot study

Abstract – Background: Mineral trioxide aggregate (MTA) is a multi‐purpose dental material with various uses in dentistry. Iodine potassium iodide (IKI) is the most commonly used iodine compound in endodontics. We aimed to assess the antimicrobial activity of tooth‐colored ProRoot MTA combined with IKI. Materials and methods: The antimicrobial activity of IKI was assessed at three concentrations (1%, 2%, and 4%) as the mixing agents combined with MTA against Enterococcus faecalis, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans. For each microorganism, three plates were inoculated with 100 μl of a microbial suspension (McFarland 0.5). Four wells were prepared in each plate. MTA (70 mg) was mixed with any of the three concentrations of IKI (25 μl) or sterile distilled water (25 μl) and placed in each well. The plates were incubated for 24 h at 37°C. Zones of inhibition (ZOI) were measured in millimeters by a blinded observer. Data were analyzed using analysis of variance and the Dunnett t‐test. Results: All MTA mixtures with water or IKI solutions showed inhibitory zones. The mean ZOI of each MTA/IKI mixture was not significantly different from MTA/water mixture (P > 0.05). MTA/1% IKI had smaller ZOI than MTA/water against E. coli, E. faecalis, and C. albicans. MTA/2% IKI showed larger ZOI only against P. aeruginosa. MTA/4% IKI showed larger ZOI against P. aeruginosa and E. coli (P < 0.05). Conclusions: Substitution of IKI solutions (1%, 2%, and 4%) for water did not significantly increase the antimicrobial activity of MTA.     

Evaluation of Cytotoxicity and Physicochemical Properties of Calcium Silicate-based Endodontic Sealer MTA Fillapex

IntroductionThe aim of the study was to evaluate the cytotoxicity, radiopacity, pH, and flow of a calcium silicate–based and an epoxy resin–based endodontic sealer, MTA Fillapex (Angelus, Londrina, PR, Brazil) and AH Plus (Dentsply, Konstanz, Germany), respectively.MethodsCytotoxicity, radiopacity, and flow evaluation were performed following ISO requirements. The pH level was measured at periods of 3, 24, 72, and 168 hours. Cytotoxicity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay to check the Balb/c 3T3 cells viability at 1- to 4-week periods. Data were statistically analyzed by analysis of variance and the Tukey test with a significance level of 5%.ResultsIn all tested periods, MTA Fillapex was more cytotoxic than AH Plus (P < .05). Although AH Plus presented higher radiopacity than MTA Fillapex (P < .05), both sealers showed minimum required values. MTA Fillapex presented alkaline pH in all experimental times, whereas AH Plus cement showed a slightly neutral pH and a flow significantly lower than that of MTA Fillapex (P < .05).ConclusionsAlthough MTA Fillapex was more cytotoxic than AH Plus, it showed suitable physicochemical properties for an endodontic sealer.     

Effect of phytic acid on the setting times and tensile strengths of calcium silicate‐based cements

This study aimed to evaluate and compare the effect of 1% phytic acid as a mixing medium on the setting times and diametral tensile strengths of different calcium silicate‐based cements. Specimens for four experimental groups (n = 20/each) were fabricated by mixing ProRoot MTA^® (Dentsply) and Biodentine^® (Septodont) powders with their original liquids or with 1% phytic acid. Half of the samples in each group were immediately subjected to setting time tests, whereas the remaining half was subjected to the diametral tensile strength test after 3 weeks. When mixed with their original liquids, the setting time of MTA was significantly longer than that of Biodentine^® (P < 0.05). When mixed with phytic acid, the initial and final setting times of both test materials significantly decreased (P < 0.05). The diametral tensile strength of Biodentine^® was significantly greater than that of MTA (P < 0.05). However, phytic acid had no effect on this outcome (P > 0.05).     

Chemical-physical Properties and Apatite-forming Ability of Mineral Trioxide Aggregate Flow

Introduction

This study aimed to analyze the chemical-physical properties, including pH, volumetric change, radiopacity, and apatite-forming ability in simulated body fluid, of a new tricalcium silicate material (MTA Flow; Ultradent Products Inc, South Jordan, UT).

Effects of two fast-setting calcium-silicate cements on cell viability and angiogenic factor release in human pulp-derived cells

Mineral trioxide aggregate (MTA) is considered a pulp-capping agent of choice, but has the drawback of a long setting time. This study aimed to assess two different types of calcium-silicate cements as pulp-capping agents, by investigating their in vitro cytotoxicity and angiogenic effects in human pulp cells. ProRoot MTA, Endocem Zr, and Retro MTA were prepared as set or freshly mixed pellets. Human pulp-derived cells were grown in direct contact with these three cements, Dycal, or no cement, for 7 days. Initial cell attachment, viability, calcium release, and the levels of vascular endothelial growth factor (VEGF), angiogenin, and basic fibroblast growth factor (FGF-2) were evaluated statistically using a linear mixed model (P < 0.05). The biocompatibility of Retro MTA was similar to those of the control and ProRoot MTA. Endocem Zr groups showed fewer and more rounded cells after a 3-day culture; however, the initial cytotoxicity appeared transient. All test materials showed significant increases in calcium concentration compared with the control group (P < 0.05). VEGF and angiogenin levels in ProRoot MTA and Retro MTA groups were significantly higher than those in the Endocem Zr group (P < 0.05). FGF-2 levels were not significantly different between groups (P > 0.05). We demonstrate that Retro MTA, which has a short setting time, has similar biocompatibility and angiogenic effects on human pulp cells, and can therefore potentially be as effective in pulp capping as ProRoot MTA. Endocem Zr showed intermittent cytotoxicity and elicited lower levels of VEGF and angiogenin expression.     

Comparison of the Biological Properties of ProRoot MTA,OrthoMTA, and Endocem MTA Cements

Introduction

OrthoMTA (BioMTA, Seoul, Korea) and Endocem MTA (Maruchi, Wonju-si, Korea) were recently developed to overcome the disadvantages of ProRoot MTA (Dentsply, Tulsa, OK). This study aimed to compare the biological properties of OrthoMTA and Endocem MTA with those of ProRoot MTA using the preosteoblastlike cell line MC3T3-E1.

Methods

The setting times of calcium silicate–based cements (CSCs) and their effects on the pH of distilled water during storage were determined according to ISO standards. MC3T3-E1 cells were cultured with ProRoot MTA, OrthoMTA, and Endocem MTA. The viability of the cells was assessed using the Cell Counting Kit-8 assay (Dojindo Laboratory, Kumamoto, Japan) on the supernatants of CSCs, and the cells' osteopontin production was determined by an enzyme-linked immunosorbent assay on a culture with the materials on days 3 and 7 of incubation.

Results

Endocem MTA exhibited a significantly shorter setting time (15.3 ± 0.5 minutes) than did ProRoot MTA and OrthoMTA (318.0 ± 56.0 and 324.3 ± 2.1 minutes, P < .05). Additionally, all CSCs caused their storage water to become highly alkaline after 7 days. OrthoMTA was significantly more cytotoxic than ProRoot and Endocem MTA (P < .05). ProRoot MTA induced significantly more OPN production than OrthoMTA and Endocem MTA on both days 3 and 7 (P < .05).

Conclusions

ProRoot MTA appeared to be superior to OrthoMTA and Endocem MTA in terms of biological properties although Endocem MTA exhibited the shortest setting time and presented lower cytotoxicity with osteoblastlike cells.     

Short‐term antimicrobial properties of mineral trioxide aggregate with incorporated silver‐zeolite

Abstract – The purpose of this in vitro study was to determine whether adding silver‐zeolite (SZ) to mineral trioxide aggregate (MTA) would enhance the antimicrobial activity of MTA against Staphylococcus aureus (ATCC #25923), Enterococcus faecalis (ATCC #29212), Escherichia coli (ATCC#25922), Pseudomonas aeruginosa (ATCC #27853), Candida albicans (ATCC #90028), Porphyromonas gingivalis (ATCC #33277), Actinomyces israelii (ATCC #12102), and Prevotella intermedia (ATCC# 15032). SZ was added at 0.2% and 2% mass fraction concentration to MTA powder. The control group was MTA powder with no SZ. The antimicrobial effect test was accomplished by placing freshly mixed MTA specimens on agar plates inoculated with microorganisms and comparing the zones of inhibition at 24, 48, and 72 h. The amounts of silver ion release from MTA specimens were measured with atomic absorption spectrophotometry at 10‐min, 24‐, 48‐, and 72‐h periods. The pH of MTA specimens was measured with a pH meter at 10‐min, 24‐, 48‐, and 72‐h periods. MTA with 2% and 0.2% SZ specimens showed inhibitory effects on some microorganisms at all time periods, whereas no antimicrobial activity showed for P. intermedia and A. israelii. MTA without SZ inhibited C. albicans, E. Coli, and P. intermedia. The highest silver release was detected in 2% SZ MTA at 24 h. The incorporation of SZ may enhance the antimicrobial activity of MTA.