The mica-based glass-ceramics were prepared in the SiO-AlO-MgO-MgF-SrCO-CaCO-CaF-PO glass system. There were four mica-based glass-ceramics produced in this study according to the pigment added (CeO or Pr-ZrSiO/Fe-ZrSiO) and crystallization time (5-35 min). Four dental glass-ceramics, which were leucite-based, lithium disilicate-based and two zirconia reinforced lithium silicate ceramics, were also tested. The phase identification of mica-based glass-ceramics was performed using an X-ray diffractometer. The fracture toughness (K) was determined using the fractographic analysis approach. The one-way ANOVA was used to analyze the significant differences among the obtained K values at a=0.05. The results from the phase analysis showed that the mica glassceramics consisted of calcium-mica, fluorapatite and strontiumapatite. The K of mica-based glass-ceramics ranged between 1.36 to 1.53 MPa•m which were superior to only that of a leucite-based glass-ceramic. The shade and translucency of mica-based glassceramics appeared to be acceptable for dental application when compared with other dental glass-ceramics.
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http://dx.doi.org/10.4012/dmj.2018-077 | DOI Listing |
Dent Mater J
June 2019
Department of Prosthodontics, Faculty of Dentistry, Mahidol University.
The mica-based glass-ceramics were prepared in the SiO-AlO-MgO-MgF-SrCO-CaCO-CaF-PO glass system. There were four mica-based glass-ceramics produced in this study according to the pigment added (CeO or Pr-ZrSiO/Fe-ZrSiO) and crystallization time (5-35 min). Four dental glass-ceramics, which were leucite-based, lithium disilicate-based and two zirconia reinforced lithium silicate ceramics, were also tested.
View Article and Find Full Text PDFDent Mater
February 2007
State Key Laboratory for Powder Metallurgy, Central South University, Changsha, 410083 Hunan, PR China.
Objectives: The aim of this study was to prepare mica-based glass-ceramics containing needle-like fluorapatites, and to understand the relationship between the composition, the microstructure and mechanical properties.
Methods: The specimens were prepared by casting and subsequent heat treatment. The crystalline phases in the specimens were determined by X-ray diffraction (XRD).
J Biomed Mater Res B Appl Biomater
July 2004
Section of Restorative Dentistry and Prosthodontics, College of Dentistry, The Ohio State University, 305 West 12th Avenue, Box 191, P.O. Box 182357, Columbus, Ohio 43218, USA.
Previous work has shown that heat pressing of mica-based glass-ceramics can lead to crystal alignment along the direction of pressing. The purpose of this study was to evaluate the effect of heat pressing on the fracture toughness of mica-based glass-ceramics. Glass rods (12 x 60 mm) were prepared by melting the glass composition at 1400 degrees C for 2 h.
View Article and Find Full Text PDFSheng Wu Yi Xue Gong Cheng Xue Za Zhi
February 2004
Department of Biomedical Engineering, Sichuan University, Chengdu 610065, China.
The phase constitution, microstructure and properties of a new type of machinable glass-ceramics containing fluorophlogopite-type (FPT) Ca-mica for used in restorative dentistry were investigated. According to the results of X-ray diffraction (XRD) and energy-dispersive spectrometry(EDS), its main crystalline phases were FPT Ca-mica and t-ZrO2, together with few KxCa(1-x)/2Mg2Si4O10F2, m-ZrO2. The flexible strength was 235 MPa, which was nearly two times larger than that of the present mica-based dental materials, and the highest fracture toughness was 2.
View Article and Find Full Text PDFJ Biomed Mater Res B Appl Biomater
February 2003
College of Dentistry, Section of Restorative Dentistry, Prosthodontics, and Endodontics, The Ohio State University, 305 West 12th Avenue, Box 191, P.O. Box 182357, Columbus, Ohio 43218, USA.
The purpose of this study was primarily to determine the feasibility of heat-pressing a mica-based glass-ceramic with the use of commercially available dental equipment, and secondly to evaluate the effect of various processing variables on the degree of crystal alignment in the pressed glass-ceramic. The hypotheses were that the mica-based glass-ceramic could be successfully heat-pressed and that some degree of crystal orientation would be obtained, depending on the processing variables. The glass composition was melted at 1400 degrees C for 2 h and cast into 12 x 60-mm rods.
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