Context: Furcal perforation is a common occurrence during endodontic treatment. Prompt intervention and use of proper repair materials are very important to improve the prognosis of involved tooth. Material qualities are also determining factor of success. Search for newer materials that are easy to manipulate, cost effective with better physical and biological properties is a never-ending process. Objective: The aim of the present in vitro study was to evaluate the sealing ability of ProRoot MTA, biodentine, and bone cement as furcation repair materials in molar teeth using dye penetration method analyzed under the stereomicroscope. Materials and Methods: A total of 45 recently extracted mandibular molars with non-fused well-developed roots were collected and intentional furcation perforations were made with a bur and perforations were treated with ProRoot MTA, biodentine, and bone cement. These specimens were then immersed in Rhodamine B dye. After their removal, dye penetration was evaluated after longitudinal sectioning of the teeth under the stereomicroscope. Results: The results showed that furcation perforation repaired with biodentine showed decrease in microleakage compared with that of ProRoot MTA and bone cement. However, there was no statistically significant difference between the ProRoot MTA and biodentine. Conclusion: Biodentine is a promising material for furcation repair as it overcomes some of the disadvantages of ProRoot MTA such as long setting time and poor handling characteristics.
The values of the shear bond strength and the statistical evaluation are given in Table 1. At all observation pe- riods ProRoot MTA showed the lowest shear bond strength of all tested materials. After two days a slight touch with the metal plunger was effectual to detach all ProRoot MTA samples from the dentine surface. Thus, shear bond strength was not measurable and set to be “0”. Although the dentine bonding of ProRoot MTA in- creased over time after 14 d still 20% of the specimens showed no measurable bonding to the dentine surface. The shear bond strength for Biodentine after 2 d was nearly 3 MPa and tripled within one week to more than 9 MPa. The GIC ChemFil rock reached a shear bond strength of about 10 MPa after two days which was comparable to the values determined after one and two weeks. Hence, an in- or decrease of the values did not occur over time. The composite resin X-trabase univer- sal in combination with the dentine adhesive Futurabond DC showed mean shear bond strengths of about 30 MPa with no significant changes over time.
Results: OrthoMTA had the highest antibacterial activity against Pi. The mean number of CFU/ml of Fn in the presence of ProRoot MTA and RetroMTA was significantly lower than that in positive controls. There were significant differences between the antibacterial activities of ProRoot MTA and OrthoMTA against Pg compared to positive controls. Conclusions: ProRoot MTA, OrthoMTA, and RetroMTA had similar antibacterial activities against the three evaluated anaerobic endodontic bacteria, except RetroMTA against Pg. Key words: Bacterial Sensitivity Test; Mineral Trioxide Aggregate; OrthoMTA; ProRoot MTA; RetroMTA
The null hypothesis of this study has to be rejected as Biodentine and ProRoot MTA showed marked differ- ences in their physicochemical properties. Concerning solubility, both materials fulfilled the requirements of ISO 6876:2001  but Biodentine was significantly more soluble than ProRoot MTA. The increased solubil- ity may be an advantage in regard to bioactivity, but further research is necessary. Biodentine possess a sig- nificantly higher Vickers microhardness compared to ProRoot MTA. Hence, concerning surface hardness this cement may be denoted as a dentine substitute. The radioopacity value of Biodentine was significantly lower than that of ProRoot MTA and not in accordance with ISO 6876 . The radiodensity of Biodentine should be improved. The setting time of Biodentine is significantly lower than that of ProRoot MTA, which may be an advantage in clinical practice.
during setting , powder to water ratio, size of the particles and also the setting temperature. When Amalgam, IRM and MTA were tested for repair of experimentally created root perforations, results showed that the MTA had significantly less microleakage than IRM or Amalgam. 112 According to Weldon JK et al., the combination of MTA and Super EBA provided a more rapid seal than MTA alone. 125 White ProRoot MTA was used in sealing the perforations of teeth in a study by Chang et al, which contained significantly less arsenic, lead, chromium than Portland cement and it was concluded that purity 21 of White ProRoot MTA and Portland cement was not comparable. White MTA contains much less iron than gray MTA. 117 In this study White ProRoot MTA was used as the repair material for group 1 samples.
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AH Plus, an epoxy resin-based sealer with broad clin- ical applications, is accepted to be the golden standard against which all new sealers are compared with [8–10]. The antimicrobial activity of AH Plus has been widely investigated. Studies have showed that AH Plus inhibited the growth of both bacteria and fungi significantly [1, 11–13]. ProRoot MTA, a calcium silicate–based material with various clinical applications was chosen in the present study, as it is the bioceramic cement to which new root-end filling materials are being compared [14– 16]. The antimicrobial effect of MTA has been reported but with controversial results [14–16]. Limited informa- tion was obtained regarding the antimicrobial activity of RealSeal sealer, a third generation of multi-methacrylate resin-based material, containing bioactive glass, calcium hydroxide, and radiopaque filler [17, 18].
ProRoot MTA does not contain calcium phosphate, calcium oxide or silica. Calcia, alumina and silica are the primary ingredients of portland cement. The typical portland cement contains about only 0.2% of phosphate. ProRoot MTA was developed for reducing discoloration to the tooth structure. It eliminated C4AF (tetracalciumaluminoferrite) as iron (Fe)’s main discoloration induced element.; The neurotoxicity of calcium aluminate compounds has not been demonstrated; However some studies have shown an increased risk of developing Alzheimer’s disease with environmental factors such the intake of metals, particularly aluminium 9-11 .
Material and methods. Human dental pulp cells isolated from dental pulps were cultured in standard culture conditions in Dulbecco’s Modified Eagle’s Medium (DMEM) and then the effects of Micro-Mega mineral trioxide aggregate (MM-MTA) (Micro-Mega, Besançon, France) and ProRoot MTA (MTA) (Dentsply Sirona, Tulsa, USA) (positive control) were evaluated on HDPCs at 1, 7 and 14 days. Untreated cells were used as a negative control. Odontoblastic differentiation was assessed by alkaline phosphatase (ALP) activity. Runt- related transcription factor 2 (RUNX2), alkaline phosphatase liver/bone/kidney (ALPL), bone morphogenetic protein 2 (BMP2), dentin sialophosphoprotein (DSPP), and Distal-less homeobox 3 (DLX3), as odontoblastic/ osteoblastic expression markers, were evaluated by semi-quantitative real-time polymerase chain reaction (RT-PCR) analysis. Calcium levels of culture media were also determined.
General anesthesia was performed through intra-muscular injection of ketamine hydrochloride (Ketlar 0.5%) v, 20 mg / kg body weight, and xylazinevi (1 mg / kg body weight). After routine disinfection, and preparation of surgical field by betadine, an extra-oral submandibular incision was performed at the inferior border to raise a full thickness skin flap. The masseter muscle was incised and dissected from periosteum to expose the body of the mandible. By using low– speed round bur number 2, with copious irrigation, a surgical bony defect of ≈ 1 mm. in diameter and depth was done. The materials were mixed, delivered, and compacted into the prepared osteotomies according to the manufactures recommendation. MM-MTA was placed in the right side of the mandible and the Grey ProRoot MTA was placed in the left side. . After implantation, the soft tissues were held in place with a 3-0 polyglycolic acid resolvable suture material, and a fluid tight seal was obtained with histoacryl (El-Sweifyet al., 2008).
We have previously demonstrated that accumulation of persistent DNA damage leads to a cell cycle arrest and induction of senescence in A549 cells . Thus, we determined the effect of the different treatment regimens on H2AX phosphorylation. Analysis of the total popu- lation revealed that irradiation with 5 Gy IR resulted in phosphorylation of H2AX in more than 90 % of the cells irrespective if MTA was administered concomitantly or as pretreatment (Fig. 4a). MTA-alone treatment for 24 h only marginally increased γH2AX levels in the total pop- ulation (treatments #2 and 3, day 0 ➙ 1) (Fig. 4a). How- ever, analysis of the cell cycle specific subpopulations revealed that MTA-alone treatment slightly increased γH2AX levels in S-phase and G2/M-phase cells whereas cells in the G1-phase were not affected (Fig. 4b). MTA treatment for 48 h (treatment #3, day 2) resulted in robust H2AX phosphorylation in a fraction of S-phase cells (34 %), which was also observed in the majority of cells in the G2/M-phase (66 %). After MTA-IR co-treatment, H2AX was rapidly phosphorylated in the majority of cells in all cell cycle phases (93 % of total population) (treat- ment #1, day 1, Fig. 4a). 24 h after irradiation, γH2AX phosphorylation returned to basal levels even in the pres- ence of MTA co-treatment (treatment #1, day 0 ➙ 1). Similarly, H2AX phosphorylation was increased to nearly maximal levels in all phases of the cell cycle when irra- diation was preceded by 48 or 71 h MTA pretreatment (91 and 97 % of total population, respectively) (treat- ment #2, day 2 and treatment #3, day 3, respectively). H2AX phosphorylation also returned to basal levels 24 h after irradiation during treatment #2 (treatment #2, day 2 ➙ 3). However, H2AX phosphorylation levels were still increased 3 and 6 days after termination of treatment #3 (day 6 and 9, respectively) compared to treatment #1 (25.7 and 20.5 % for treatment #3 compared to 16.5 and 6.0 % for treatment #1, respectively, P < 0.05) (Fig. 4a).
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cytotoxicity and cell attachment in vitro. Cell viability was determined at 24 hr, 3 days and 7 days by using a 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)- 2H-tetrazolium-5-carboxanilide (XTT) assay with material extracts. Cell adhesion was examined with a scanning electron microscope on the surface of materials at 24 and 48 hr. Angelus MTA displayed the lowest cell viabilities at all-day incubations. Endocem had high biocompatibility on the first day. After culturing for 3 days and 7 days, the cell viabilities of Biodentine, Endocem and MM-MTA had similar results, and their cell viability was significantly higher than that of Angelus. No definite relation was found between the incubation time and the relative cell viability in any group. In scanning electron micrographs, the cells were attached to the material surface for all materials, although the cells in the Biodentine group were attached better than the other groups on the second day. Cell viability and cell attachment was lower in the Angelus group The study concluded that Endocem, Biodentine and MM-MTA were similar in biocompatibility and cytotoxicity.
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Abstract—This paper focuses on peaking and splitting phe- nomena of waves, in order to support hydrodynamic laboratory activities for generating waves which have large amplitude and are very steep but do not break during their propagation in the wave tank. Such waves, called extreme waves or giant waves, will be used to test oceanic objects, like ships and marine structures, before they operate in real condition. The previous study shows that nonlinear effects will deform the initial wave and may lead to large waves with height larger than twice as high as the original input; the deformation is followed by peaking and splitting phenomena. It is interesting to understand and quantify the nonlinear effects; it is also interesting to know at which location in the wave tank, the extreme position, the waves will achieve their maximum amplitude and how high the magnitude of the amplitude at this position. As in the previous research, a quantity that can be used to investigate these phenomena is Maximal Temporal Amplitude (MTA). MTA can be used to measure the maximum amplitude amplification of the wave elevation at each location during the observation time. It is known that an explicit expression of the MTA can not be found in the general form of the governing equations (the full Euler equations with the exact kinematic and dynamic free surface conditions) and generating signals. Simplified models, like Boussinesq, Korteweg de Vries (KdV) and Non Linear Schrodinger (NLS) type of equations which have in common that the fluid motion in the layer is approximated to arrive at equations at the free surface alone are considered. By using the third order approximation of KdV (TOA-KdV) or Boussinesq (TOA-Bouss) and MTA, it is obtained a formula that can be used to predict the extreme position. Furthermore, the fifth order approximation of KdV (FOA-KdV) and MTA is used to investigate the amplitude amplification, and the order of amplitude amplification factor (AAF ) is obtained. The AAF here is the ratio of the amplitude at maximum location to the initial amplitude. However, the AAF which is calculated using FOA-KdV does not match the experimental results. Therefore, in this paper we use Boussinesq model with full dispersion and the same method and procedure with the previous research. Furthermore, we verify our theoretical results using analytical and numerical as well as experimental results.
to 4 h [2, 3, 28], which compromises the application, espe- cially in supracrestal areas. The possibility of the material being washed out at cervical/furcal area during the long setting time needs to be considered . In addition, early occlusal pressure directed to the material, even in a deeper location, may compromise the integrity of the seal . Therefore, a bioceramic material that has optimal mech- anical behavior and sets fast, would be attractive to the clinician in specific clinical situations. G-MTA and W- MTA were chosen in the present study as gold standard materials because they are widely used for retrograde fill- ing, apexification and perforation repair in endodontic treatment. Although the details of the reaction mecha- nisms of the new CPSCs remain unknown, the results of the present study showed that iRoot FS had the shortest setting time of the CPSCs and HCSCs. The shortest set- ting time of iRoot FS may benefit some clinical challenge cases with time demanding. However, clinical study is still required to evaluate its performance.
MTA contains fine hydrophilic particles like calcium hydroxide and silicon which has the ability to set in the presence of wet environment.  There are various studies on the influence of blood on properties of MTA. An in vitro study by Salem MA et al., reported that exposure to blood during setting has an adverse effect on marginal adaptation and the surface microstructure of MTA.  Therefore, by addition of the accelerators reduces the infusion of the blood into the material thereby protecting it from deleterious effect by improving its initial strength. Recently, Biodentine has been used as a dentine replacement material in large carious lesions. On hydration reaction, tricalcium silicate produces calcium silicate gel and calcium hydroxide and they may precipitate at the surface. So, the unreacted tricalcium silicate grains are surrounded by hydrated calcium silicate gel, which are impermeable to water and decreases the setting reactions. 
2 | P a g e purpose in endodontic surgery such as gold foil, Gutta percha, amalgam, cavit, glass ionomer cements, composite resins, carboxylate cements, intermediate restorative material (IRM), Super EBA, zinc phosphate cements, zinc oxide eugenol cements , Biodentine and Mineral trioxide aggregate (MTA) 48,65,23 . Due to certain disadvantages like corrosion, mercury toxicity, delayed expansion (zinc containing alloys), microleakage, usage of amalgam as retrograde filling is limited. In order to overcome this disadvantage various other materials were developed like super EBA and IRM 8 . Though MTA, Biodentine, Super EBA, Glass ionomer cement are used commonly but none of this material fulfils the requirement of ideal retrograde material 20 .
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We examined the hypothesis that respiratory sinus arrhythmia (RSA) is primarily a central phenomenon and thus that RSA is directly correlated with respiratory controller output. RSA was measured in nine anesthetized dogs, first during spontaneous breathing (SB) and then during constant flow ventilation (CFV), a technique whereby phasic chest wall movements and thoracic pressure swings are eliminated. Measurements of the heart rate and of the moving time averaged (MTA) phrenic neurogram during these two ventilatory modes were made during progressive hypercapnia and progressive hypoxia. RSA divided by the MTA phrenic amplitude (RSAa) showed a power-law relationship with both arterial carbon dioxide partial pressure (PaCO2) and oxygen saturation (SaO2), but with different exponents for different conditions. However, the power-law relation between RSAa and respiratory frequency had an exponent indistinguishable from -2 whether hypoxia or hypercapnia was the stimulus for increased respiratory drive, and during both CFV and spontaneous breathing (-1.9 +/- 0.4, hypoxia, SB; -1.8 +/- 0.7, hypoxia, CFV; -2.1 +/- 0.8, hypercapnia, SB; -1.9 +/- 0.7, hypercapnia, CFV). We conclude that respiratory sinus
MTA is a powder consisting of tricalcium silicate, dicalcium silicate, tricalcium aluminate, calcium sulfate dehydrate and bismuth oxide. When the material is hydrated, it becomes a colloidal gel that solidifies in approximately 3 hours . Like Ca (OH)2, MTA also has a high pH (12.5) that causes denaturation of adjacent cells, tissues proteins, and some bacteria in the wound area. As the material sets, however, the pH changes and the cell injuries subside . The set material has low solubility and a radiopacity slightly greater than that of dentin. MTA has been found to have a set compressive strength of about 70 MPa. This is approximately equal to that of IRM .
This study shows that the reduction in bacterial inhibition was higher in AH plus group than CRCS and MTA from 24 hours to seven days and the change was statistically significant [Table/ Fig-5]. The correlation analysis showed that a significant correlation with antibacterial property was found in AH plus, CRCS and MTA Fillapex at 24 hours. However, no such significant association was observed at seven days. This shows that resin based sealers are more effective in fresh mixed state and their antibacterial activity reduces over time. Similar results were also reported in other studies [16,17].
Sealer sehr weit in die Dentintubuli penetrieren und eine hohe Oberflächenbenetzung aufweisen, gleichzeitig auch die insgesamt dichtesten Wurzelfüllungen darstellen. Laut De-Deus gibt es keine Korrelation zwischen der Penetrationstiefe eines Sealers in die Dentintubuli und der Dichtigkeit der Wurzelfüllung (De-Deus et al., 2012). ProRoot®MTA, welches in unserem Versuch die höchste Oberflächenbenetzung erzielt hat, das heißt höchster penetrierter Umfang und Total Fill® BC Sealer™, welcher die tiefsten Penetrationstiefen aufwies, wären die potenziell vielversprechendsten Sealer für einen der oben genannten Dichtigkeitstests. Somit könnte bewiesen werden, ob eine dieser beiden Größen einen signifikanten Einfluss auf die Dichtigkeit einer Wurzelkanalfüllung ausübt.
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Based on the prolonged setting time and handling difficulty of conventional MTA (ProRoot-MTA), fast setting NeoMTA Plus was developed to offer its bioactive and osteogenic potential. It was reported that there was some variation of their constituents as NeoMTA Plus contained higher aluminum and sulfur than conventional MTA that might interfere with its biological behavior . There has been scarcity of studies evaluating their biocompatibility and bioactivity. In a previous in-vitro study, the evidence of bioactivity of NeoMTA Plus was reported as the calcium phosphate crystals precipitated on the material surface . The current study was designed to evaluate their bioactivity on stem cells, and their ability to induce osteogenic differentiation when used as a root repair material.