Bioactivity evaluation of calcium silicate‐based endodontic materials used for apexification

ABSTRACTCement-based materials used in the construction of the repository for high/low level radioactive wastes may produce a highly alkaline calcium-rich groundwater (plume). The Ca ions react with soluble silicic acid, depositing calcium-silicate-hydrate (CSH) gel on the surfaces of the groundwater flow-paths and decreasing the permeability of the bedrock. Such a decrement of permeability may play a role in retarding the migration of radionuclides. In this study, the deposition behavior in a fracture was experimentally examined by using a micro flow-cell consisting of silicon plate (including a slit (60 mm×5 mm, or 60 mm×2 mm)) and granite-chip. The initial equivalent-aperture based on the square law was estimated in the range of 26 μm to 45 μm from the flow test of pure water.In the experiments, a Ca(OH)2 solution of 6.36 mM (pH: 12.2 to12.5, including NaOH) was continuously injected into the flow system at a constant flow rate of 1 or 2 ml/h. The solution flowed on the surface of the granite-chip. In this study, we prepared two kinds of chips that differed in the treatment of the surface. One chip was roughly ground with #2000 sandpaper (hereinafter referred to as rough surface) and another was polished to mirror-like surface. As a result, on the rough surface the deposits of CSH gel appeared along flow-channels across mineral grain-boundaries, while the deposits on the mirror-like surface were relatively uniform. Furthermore, the permeability in the case of rough surface became smaller than that in the case of mirror-like surface, showing the repeats of rapid decrement and increment due to the relatively large roughness of the surface. In order to estimate the decrement degrees of permeability, a simple, one-dimensional mathematical model is proposed in this study.

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Comparative evaluation of volumetric changes of three different retrograde calcium silicate materials placed under different pH condititions

BMC Oral Health ◽

10.1186/s12903-020-01325-x ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

So Yeon Kwon ◽

Min-Seock Seo

Keyword(s):

Calcium Silicate ◽

Room Temperature ◽

Volume Ratio ◽

Acidic Environment ◽

Micro Ct ◽

Micro Computed Tomography ◽

Saline Environment ◽

Significant Difference ◽

Calcium Silicate Cements ◽

Materials Used

Abstract Background The present study aimed to compare the volumetric changes of three calcium silicate cements after retrofilling and placing under different pH conditions via micro-computed tomography (micro-CT) scan. Methods Forty-two extracted human single-rooted teeth were randomly assigned to three groups according to the retrofilling materials used (Biodentine, Endocem MTA, and ProRoot MTA). Each group was divided into two subgroups according to the setting condition. The teeth in one group were immersed in normal saline for 5 days at room temperature, and the teeth in the other group were immersed in butyric acid (pH = 5.4) for 5 days at room temperature. The volume ratios of the retrofilling material were calculated via micro-CT imaging. Results The volume ratios of the Biodentine and Endocem MTA groups were significantly different between the two setting environment, and these groups had significantly lower filled volume ratio (Vf, %) in the acidic environment than in the saline environment (pH = 5.4). Meanwhile, the volume ratio of the ProRoot MTA group did not significantly differ between the two setting environments. All materials under the acidic setting condition had relative radiolucency in the area in contact with the acidic solution. Conclusion The Vf ratio of the Biodentine and Endocem MTA cements was significantly lower in the acidic environment than in the saline environment. No statistically significant difference was observed in the Vf ratio of ProRoot MTA between the two setting environments.

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Comparison of Volume Changes in Different Environmental Conditions After Retrofilling Using Three Calcium Silicate Cements

10.21203/rs.3.rs-25216/v1 ◽

2020 ◽

Author(s):

so yeon kwon ◽

minseock seo

Keyword(s):

Calcium Silicate ◽

Room Temperature ◽

Volume Ratio ◽

Acidic Environment ◽

Micro Computed Tomography ◽

Saline Environment ◽

Sealing Ability ◽

Significant Difference ◽

Calcium Silicate Cements ◽

Materials Used

Abstract Background The present study aimed to compare the marginal sealing ability of three calcium silicate cements after retrofilling at different pH levels via micro-computed tomography (CT) scan.Methods Forty-two extracted human single-rooted teeth were randomly assigned to three groups according to the retrofilling materials used (Biodentine, Endocem MTA, and ProRoot MTA). Each group was divided into two subgroups according to the setting condition. The teeth in one group were immersed in normal saline for 5 days at room temperature, and the teeth in the other group were immersed in butyric acid (pH = 5.4) for 5 days at room temperature. To investigate marginal sealing ability, the volume ratios of the retrofilling material were calculated via micro-CT imaging.Results The volume ratios of the Biodentine and Endocem MTA groups were significantly different between the two setting environment, and these groups had significantly lower filled volume ratio (Vf, %) in the acidic environment than in the saline environment (pH = 5.4). Meanwhile, the volume ratio of the ProRoot MTA group did not significantly differ between the two setting environments. All materials under the acidic setting condition had relative radiolucency in the area in contact with the acidic solution.Conclusions The Vf ratio of the Biodentine and Endocem MTA cements was significantly lower in the acidic environment than in the saline environment. Meanwhile, no statistically significant difference was observed in the Vf ratio of ProRoot MTA between the two setting environments.

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Ion release and mechanical properties of calcium silicate and calcium hydroxide materials used for pulp capping

International Endodontic Journal ◽

10.1111/iej.12281 ◽

2014 ◽

Vol 48 (1) ◽

pp. 89-94 ◽

Cited By ~ 34

Author(s):

L. C. Natale ◽

M. C. Rodrigues ◽

T. A. Xavier ◽

A. Simões ◽

D. N. de Souza ◽

...

Keyword(s):

Mechanical Properties ◽

Calcium Hydroxide ◽

Calcium Silicate ◽

Ion Release ◽

Pulp Capping ◽

Materials Used

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Tooth discoloration effects of calcium silicate based barrier materials used in revascularization and treatment with internal bleaching

Journal of Dental Sciences ◽

10.1016/j.jds.2017.03.009 ◽

2017 ◽

Vol 12 (4) ◽

pp. 347-353 ◽

Cited By ~ 3

Author(s):

Makbule Bilge Akbulut ◽

Arslan Terlemez ◽

Melek Akman ◽

Begum Buyukerkmen ◽

Mehmet Burak Guneser ◽

...

Keyword(s):

Calcium Silicate ◽

Barrier Materials ◽

Tooth Discoloration ◽

Materials Used

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Sealing ability of three different materials to repair furcation perforations using computerized fluid filtration method

Journal of Dental Research Dental Clinics Dental Prospects ◽

10.34172/joddd.2021.031 ◽

2021 ◽

Vol 15 (3) ◽

pp. 183-187

Author(s):

Cemre Koç ◽

Berna Aslan ◽

Zuhal Ulusoy ◽

Hasan Oruçoğlu

Keyword(s):

Calcium Silicate ◽

Time Interval ◽

Fluid Filtration ◽

Filtration Method ◽

Sealing Ability ◽

Repair Materials ◽

Mandibular Molar ◽

Significant Difference ◽

The Difference ◽

Materials Used

Background. The present study aimed to evaluate the sealing ability of three different calcium silicate-based materials in furcation perforations. Methods. Seventy-six human mandibular molar teeth were selected. Perforations were created in the center of the pulp chamber floor. The experimental teeth were randomly divided into three groups (n=22). Perforations were repaired with MTA Angelus, Endocem MTA, or EndoSequence BioCeramic Root Repair Material Fast Set Putty (BC-RRM Putty). Microleakage of the different repair materials to be tested was measured by computerized fluid filtration method at 24- and 72-hour intervals. Results. For each time interval, no statistically significant difference was observed between the groups. For Endocem MTA and BC-RRM Putty groups, the difference between the leakage values measured at both periods was not statistically significant (P>0.05). However, there was a significant difference for the MTA Angelus group (P<0.05). Conclusion. All the calcium silicate-based materials used in the present study showed similar performance in repairing furcation perforations at 24- and 72-hour intervals.

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Deformation Replication

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068394 ◽

1970 ◽

Vol 28 ◽

pp. 280-281

Author(s):

J. Temple Black

Keyword(s):

Cutting Speed ◽

Machining Process ◽

Depth Of Cut ◽

Rake Face ◽

Orthogonal Machining ◽

Aluminum Chips ◽

Before And After ◽

Materials Used ◽

Glass Knife ◽

Very High

Tool materials used in ultramicrotomy are glass, developed by Latta and Hartmann (1) and diamond, introduced by Fernandez-Moran (2). While diamonds produce more good sections per knife edge than glass, they are expensive; require careful mounting and handling; and are time consuming to clean before and after usage, purchase from vendors (3-6 months waiting time), and regrind. Glass offers an easily accessible, inexpensive material ($0.04 per knife) with very high compressive strength (3) that can be employed in microtomy of metals (4) as well as biological materials. When the orthogonal machining process is being studied, glass offers additional advantages. Sections of metal or plastic can be dried down on the rake face, coated with Au-Pd, and examined directly in the SEM with no additional handling (5). Figure 1 shows aluminum chips microtomed with a 75° glass knife at a cutting speed of 1 mm/sec with a depth of cut of 1000 Å lying on the rake face of the knife.

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High Voltage Transmission Microscopy of Surveyor III Camera Shrouds

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064748 ◽

1971 ◽

Vol 29 ◽

pp. 138-139

Author(s):

W. R. Duff ◽

L. E. Thomas ◽

R. M. Fisher ◽

S. V. Radcliffe

Keyword(s):

Alloy Sheet ◽

Transmission Microscopy ◽

Television Camera ◽

Window Method ◽

Transmission Electron ◽

Microstructural Effects ◽

Lunar Environment ◽

Successful Retrieval ◽

Materials Used ◽

Abrasive Paper

Successful retrieval of the television camera and other components from the Surveyor III spacecraft by the Apollo 12 astronauts has provided a unique opportunity to study the effects of a known and relatively extensive exposure to the lunar environment. Microstructural effects including those produced by micro-meteorite impact, radiation damage (by both the solar wind and cosmic rays) and solar heating might be expected in the materials used to fabricate the spacecraft. Samples received were in the form of 1 cm2 of painted unpainted aluminum alloy sheet from the top of the camera visor (JPL Code 933) and the sides (935,936) and bottom (934) of the lower camera shroud. They were prepared for transmission electron microscopy by first hand-grinding with abrasive paper to a thickness of 0.006". The edges were lacquered and the sample electropolished in 10% perchloric methanol using the “window” method, to a thickness of ~0.001". Final thinning was accomplished by polishing 3 mm punched disks in an acetic-phosphoric-nitric acid solution.

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Structure-property relationships of PE/PP sandwiched films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126998 ◽

1987 ◽

Vol 45 ◽

pp. 454-455

Author(s):

J. Petermann ◽

G. Broza ◽

U. Rieck ◽

A. Jaballah ◽

A. Kawaguchi

Keyword(s):

Mechanical Tests ◽

Polymer Materials ◽

Ionic Crystals ◽

Structure Property ◽

Polymer Systems ◽

Structure Property Relationships ◽

Oriented Films ◽

Materials Used ◽

Polymer Laminates ◽

Heated Glass

Oriented overgrowth of polymer materials onto ionic crystals is well known and recently it was demonstrated that this epitaxial crystallisation can also occur in polymer/polymer systems, under certain conditions. The morphologies and the resulting physical properties of such systems will be presented, especially the influence of epitaxial interfaces on the adhesion of polymer laminates and the mechanical properties of epitaxially crystallized sandwiched layers.Materials used were polyethylene, PE, Lupolen 6021 DX (HDPE) and 1810 D (LDPE) from BASF AG; polypropylene, PP, (PPN) provided by Höchst AG and polybutene-1, PB-1, Vestolen BT from Chemische Werke Hüls. Thin oriented films were prepared according to the method of Petermann and Gohil, by winding up two different polymer films from two separately heated glass-plates simultaneously with the help of a motor driven cylinder. One double layer was used for TEM investigations, while about 1000 sandwiched layers were taken for mechanical tests.

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