• Title/Summary/Keyword: Calcium silicate

Search Result 316, Processing Time 0.029 seconds

Chemical characteristics of mineral trioxide aggregate and its hydration reaction

  • Chang, Seok-Woo
    • Restorative Dentistry and Endodontics
    • /
    • v.37 no.4
    • /
    • pp.188-193
    • /
    • 2012
  • Mineral trioxide aggregate (MTA) was developed in early 1990s and has been successfully used for root perforation repair, root end filling, and one-visit apexification. MTA is composed mainly of tricalcium silicate and dicalcium silicate. When MTA is hydrated, calcium silicate hydrate (CSH) and calcium hydroxide is formed. Formed calcium hydroxide interacts with the phosphate ion in body fluid and form amorphous calcium phosphate (ACP) which finally transforms into calcium deficient hydroxyapatite (CDHA). These mineral precipitate were reported to form the MTA-dentin interfacial layer which enhances the sealing ability of MTA. Clinically, the use of zinc oxide euginol (ZOE) based materials may retard the setting of MTA. Also, the use of acids or contact with excessive blood should be avoided before complete set of MTA, because these conditions could adversely affect the hydration reaction of MTA. Further studies on the chemical nature of MTA hydration reaction are needed.

Evaluation of Chloride Ion Penetration Resistance of High Calcium Silicate Cement Concrete (High Sulfated Calcium Silicate 시멘트 콘크리트의 염소이온침투저항성 평가)

  • Jeong, Seok-Man;Yang, Wan-hee;Kim, Hyeon-Soo;Lee, Gun-Cheol
    • Journal of the Korea Institute of Building Construction
    • /
    • v.22 no.1
    • /
    • pp.35-43
    • /
    • 2022
  • The aim of this work was to a comparative review the performance of high calcium silicate cement (HSCSC) and that of ordinary Portland cement(OPC) and blast furnace slag cement(S/C). The result of the compressive test confirmed that the compressive strength development rate of high calcium silicate cement concrete at the age of 3 days was 73.6% that of ordinary Portland cement concrete. However, at the age of 28 days, the strength development rate of high calcium silicate cement increased to about 107.0% compared to ordinary Portland cement. In addition, the test of the chloride ion penetration resistance of concrete showed that at the age of 28 days, the passed charge decreased by 73.4% and 93.0%, respectively, in blast furnace slag cement and high calcium silicate cement compared to ordinary Portland cement, and at the age of 56 days, it decreased by 79.1% and 98.3%, exhibiting excellent resistance to chloride ion penetration. In particular, it was confirmed that the rate of decrease in the passed charge with age was higher in high calcium silicate cement than in ordinary Portland cement and blast furnace slag cement.

A Study on the High Temperature Properties of Self-hardening Sand Mold (High Temperature Properties of Self-Hardening Sand Mold using Calcium-Orthosilicate Powder) [I] (자경성 주형의 고온성질에 관한 연구 Calcium-Orthosilicate를 이용한 자경성 주형의 고온성질에 관하여 [I])

  • 강인찬;한윤희;문인탁
    • Journal of the Korean Ceramic Society
    • /
    • v.13 no.1
    • /
    • pp.20-24
    • /
    • 1976
  • These are many kinds of self-hardening methods for sand mold using sodium silicate. When sodium silicate solution is mixed with calcium-orthosilicate powder hardening reaction occurs, which is based for self-hardening method at high temperature. The high temperature strength and resicual strength of mold are related to the mole ratio of sodium silicate and the contents of calcium-orthosilicate powder. The results obtained in this study were as follows: 1) The high temperature strength of mold was maximum at about $600^{\circ}C$, and at higher temperature showed lower value on the contrary. 2) The high temperature strength of mold was increased by increasing the amount of sodium silicate having lower mole ratio and high concentration. 3) The residual strength of mold was reduced by increasing the mole ratio of sodium silicate and increasing the concentration of calcium-orthosilicate.

  • PDF

Calcium silicate-based root canal sealers: a literature review

  • Lim, Miyoung;Jung, Chanyong;Shin, Dong-Hoon;Cho, Yong-bum;Song, Minju
    • Restorative Dentistry and Endodontics
    • /
    • v.45 no.3
    • /
    • pp.35.1-35.17
    • /
    • 2020
  • Epoxy resin-based sealers are currently widely used, and several studies have considered AH Plus to be the gold-standard sealer. However, it still has limitations, including possible mutagenicity, cytotoxicity, inflammatory response, and hydrophobicity. Drawing upon the advantages of mineral trioxide aggregate, calcium silicate-based sealers were introduced with high levels of biocompatibility and hydrophilicity. Because of the hydrophilic environment in root canals, water resorption and solubility of root canal sealers are important factors contributing to their stability. Sealers displaying lower microleakage and stronger push-out bond strength are also needed to endure the dynamic tooth environment. Although the physical properties of calcium silicate-based sealers meet International Organization for Standardization recommendations, and they have consistently reported to be biocompatible, they have not overcome conventional resin-based sealers in actual practice. Therefore, further studies aiming to improve the physical properties of calcium silicate-based sealers are needed.

Treatment of Benzene Vapor Gas with Compost and Calcium Silicate Porous Biofilters (퇴비 및 규산칼슘계 다공성 바이오필터의 벤젠휘발가스 처리)

  • Park, Joon-Seok;Namkoong, Wan;Kim, Sun-A;Park, Young-Goo;Lee, Noh-Sup
    • Journal of the Korean Applied Science and Technology
    • /
    • v.22 no.1
    • /
    • pp.21-27
    • /
    • 2005
  • This study was conducted to evaluate the biofiltration treatment characteristic for benzene vapor gas. Compost and calcium silicate porous material were used as biofilter fillers. Gas velocity and empty bed retention time were 15 m/hr and 4 min, respectively. Benzene gas removal efficiency of P-Bio (calcium silicate porous material with inoculation) was the highest and maintained in over 98%. After shock input of benzene gas, the removal efficiency of P-Bio biofilter was recovered within 2 days, while 5 days were taken in CP-Bio (compost + calcium silicate porous material mixture with inoculation) and CP (compost + calcium silicate porous material mixture without inoculation) biofilters. The removal efficiency of P-Bio biofilter was near 100% in the loading rate of <$85g/m^3$(filling material)/hr, It was shown that the maximum elimination capacities of P-Bio, CP-Bio, and CP biofilters were 95, 69, and $66\;g/m^3$(filling material)/hr, respectively. Microbial number of P-Bio, which the number was the lowest at start-up, was 3 orders increased on operational day 48. $CO_2$ was generated greatly in order of P-Bio, CP-Bio, and CP biofilters.

Effect of Silicate and Lime Fertilizer on Growth of Zantedeschia aethiopica (규산질 및 석회질 비료가 칼라(Zantedeschia aethiopica) 생육에 미치는 영향)

  • Goo, Dae Hoe
    • FLOWER RESEARCH JOURNAL
    • /
    • v.16 no.3
    • /
    • pp.222-227
    • /
    • 2008
  • Objective of this Research was to determine the influence of foliar application of $CaCl_2$ or $K_2SI_2O_5$ and soil application of $CaCO_3$ or $SiO_2$ on growth and cut flower quality of Zantedeschia aethiopica 'Wedding March'. To achieve this, $CaCl_2$ or $K_2SI_2O_5$ were applied at six leaf stage with the concentration of 0.05, 0.1 and 0.2% and $CaCO_3$ or $SiO_2$ were applied as basal fertilization with the amount of 100, 200, 400kg per 10a or 50, 100, 200, 400kg per 10a respectively. Plant material was used Zantedeschia aethiopica 'Wedding March'. Among calcium chloride($CaCl_2$) and calcium carbonate($CaCO_3$), calcium chloride foliar application was more effective than calcium carbonate with basal fertilization to growth of common calla 'Wedding March'. In the 0.1% solution foliar application of calcium chloride, plant height, leaf length and length of cut-flower was more longer than control. Length of leaf petiole was more longer and leaf fresh weight was more heavier than control. The degree of petiole hardness was more effective in the 0.1% solution calcium chloride foliar application than any other treatment. In the silicate fertilization treatment, plant height of 50kg per 10a treatment was most highest as 73.9cm. also its length of leaf petiole and leaf fresh weight was more effective than any other treatment. The hardness of petiole was better in the 50kg per 10a silicate fertilizer treatment. The cell shape of leaf petiole was round and tissue was regular in the treatment of 0.1% calcium chloride and 50kg per 10a silicate fertilizer but the cell of control was irregular round type. Macro element content of calcium was more amount in the treatment of silicate 50kg per 10a basal fertilization. The infected ratio of Erwinia was no relation with lime and silicate fertilizer treatment. Lime fertilizer treatment is effective for growth and flowering of Calla than silicate fertilizer and the suitable concentration was 0.1%.

Effects of Urea, Ammonium Nitrate and Calcium Silicate on the Absorption, Translocation of Potassium and Yield of Chinese Cabbage (Brassica Perkinnensis, Var. Samjin) (요소, 질산암모늄 및 규회석분말이 칼리의 흡수 및 배추의 수량에 미친 영향)

  • Oh, Wang-Keun;Kim, Jae-Young;Kim, Sung-Bae
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.20 no.4
    • /
    • pp.337-340
    • /
    • 1987
  • This experiment was conducted on relatively acid sandy loam soil at Choong-ju campus, Kon-kuk University aimed at clarifying the influence of urea and ammonium nitrate on the effect of potassium to Chinese cabbage in soils either limed or unlimed with calcium silicate. The results are summarized as follows: a. Calcium silicate application enhanced cabbage growth and under this condition, the difference in effect of urea and ammonium nitrate can hardly be observed. b. Without calcium silicate application, the response of Chinese cabbage to ammonium nitrate was more distinctive than that to urea. This was partially attributable to the greater use of soil born potassium at ammonium nitrate treatment. c. Added potassium was not only affective in increasing cabbage yield but also contributed in improving quality of cabbage by producing greater edible portion of the cabbage. Such K effect was particularly pronounced on the acid soil where calcium silicate application was neglected. d. Potassium was easily translocated from outer leaves to inner leaves and thus, the concentration of K content in outer leaves played as a limiting factor of cabbage yield. Less than 20 me/100gr of K content in harvested dried outer leaves resulted in a linear reduction of cabbage yield.

  • PDF

X-Ray Diffraction Analysis of Various Calcium Silicate-Based Materials

  • An, So-Youn;Lee, Myung-Jin;Shim, Youn-Soo
    • Journal of dental hygiene science
    • /
    • v.22 no.3
    • /
    • pp.191-198
    • /
    • 2022
  • Background: The purpose of this study was to evaluate the composition of the crystal phases of various calcium silicate-based materials (CSMs): ProRoot white MTA (mineral trioxide aggregate) (WMTA), Ortho MTA (OM), Endocem MTA (EM), Retro MTA (RM), Endocem Zr (EN-Z), BiodentineTM (BD), EZ-sealTM (EZ), and OrthoMTA III (OM3). Methods: In a sample holder, 5 g of the powder sample was placed and the top surface of the material was packed flat using a sterilized glass slide. The prepared slides were mounted on an X-ray diffraction (XRD) instrument (D8 Advance; Bruker AXS GmbH, Germany). The X-ray beam 2θ angle range was set at 10~90° and scanned at 1.2° per minute. The Cu X-ray source set to operate at 40 kV and 40 mA in the continuous mode. The peaks in the diffraction pattern of each sample were analyzed using the software Diffrac (version 2.1). Then, the peaks were compared and matched with those of standard materials in the corresponding Powder Diffraction File (PDF-2, JCPDS International Center for Diffraction Data). A powder samples of the materials were analyzed using XRD and the peaks in diffraction pattern were compared to the Powder Diffraction File data. Results: Eight CSMs showed a similar diffraction pattern because their main component was calcium silicate. Eight CSMs showed similar diffraction peaks because calcium silicate was their main component. Two components were observed to have been added as radiopacifiers: bismuth oxide was detected in WMTA, OM, and EM while zirconium oxide was detected in RM, EN-Z, BD, EZ, and OM3. Unusual patterns were detected for the new material, OM3, which had strong peaks at low angles. Conclusion: It was caused by the presence of Brushite, which is believed to have resulted in crystal growth in a particular direction for a specific purpose.

A scientometric, bibliometric, and thematic map analysis of hydraulic calcium silicate root canal sealers

  • Anastasios Katakidis;Konstantinos Kodonas;Anastasia Fardi;Christos Gogos
    • Restorative Dentistry and Endodontics
    • /
    • v.48 no.4
    • /
    • pp.41.1-41.17
    • /
    • 2023
  • Objectives: This scientometric and bibliometric analysis explored scientific publications related to hydraulic calcium silicate-based (HCSB) sealers used in endodontology, aiming to describe basic bibliometric indicators and analyze current research trends. Materials and Methods: A comprehensive search was conducted in Web of Science and Scopus using specific HCSB sealer and general endodontic-related terms. Basic research parameters were collected, including publication year, authorship, countries, institutions, journals, level of evidence, study design and topic of interest, title terms, author keywords, citation counts, and density. Results: In total, 498 articles published in 136 journals were retrieved for the period 2008-2023. Brazil was the leading country, and the universities of Bologna in Italy and Sao Paolo in Brazil were represented equally as leading institutions. The most frequently occurring keywords were "calcium silicate," "root canal sealer MTA-Fillapex," and "biocompatibility," while title terms such as "calcium," "sealers," "root," "canal," "silicate based," and "endodontic" occurred most often. According to the thematic map analysis, "solubility" appeared as a basic theme of concentrated research interest, and "single-cone technique" was identified as an emerging, inadequately developed theme. The co-occurrence analysis revealed 4 major clusters centered on sealers' biological and physicochemical properties, obturation techniques, retreatability, and adhesion. Conclusions: This analysis presents bibliographic features and outlines changing trends in HCSB sealer research. The research output is dominated by basic science articles scrutinizing the biological and specific physicochemical properties of commonly used HCSB sealers. Future research needs to be guided by studies with a high level of evidence that utilize innovative, sophisticated technologies.