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@Article{ArataCaMaLaUsLiTa:2014:CrEv,
               author = "Arata, A. and Campos, T. M. B. and Machado, Jo{\~a}o Paulo Barros 
                         and Lazar, D. R. R. and Ussui, V. and Lima, N. B. and Tango, R. 
                         N.",
          affiliation = "{Universidade Estadual Paulista (UNESP)} and {Instituto 
                         Tecnol{\'o}gico de Aeron{\'a}utica (ITA)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and Materials Science and 
                         Technology Center (CCTM), Nuclear and Energy Research Institute 
                         and Materials Science and Technology Center (CCTM), Nuclear and 
                         Energy Research Institute and Materials Science and Technology 
                         Center (CCTM), Nuclear and Energy Research Institute and 
                         {Universidade Estadual Paulista (UNESP)}",
                title = "Quantitative phase analysis from X-ray diffraction in Y-TZP dental 
                         ceramics: A critical evaluation",
              journal = "Journal of Dentistry",
                 year = "2014",
               volume = "42",
               number = "11",
                pages = "1487--1494",
             keywords = "Artificial ageing, Y-TZP, characterisation, rietveld method.",
             abstract = "The dentistry literature shows consensus to use the Garvie and 
                         Nicholson equation modified by Toraya to quantify the Y-TZP phase 
                         transformation. However, this method does not include the 
                         possibility of cubic phase transformation and crystallographic 
                         texture after artificial ageing, and in this case, it is possible 
                         to observe errors of quantification. Objectives The aim of this 
                         study was to evaluate a dental Y-TZP ageing kinetic of phase 
                         transformation under pressure and hydrothermal conditions (130 C, 
                         2 bar) and to compare the methods of quantification by the 
                         equation of Garvie and Nicholson modified by Toraya and the 
                         Rietveld refinement method. - Methods Discs of Y-TZP (12 mm  1.2 
                         mm in height) were divided into groups (n = 4) according to the 
                         ageing times (in the range of 6 and 138 h). The superficial 
                         characterisation was made using SEM and the XDR for 
                         crystallographic analysis. Results An aggressive superficial 
                         degradation process at the beginning of phase transformation in 
                         6-10 h of ageing was observed by SEM. The phase transformation 
                         quantification showed differences between the methods. It was 
                         observed the increase and stabilisation of monoclinic phase until 
                         80% at 40 h of ageing by the Garvie and Nicholson modified by 
                         Toraya equation, compared to 60% of monoclinic phase and 
                         approximately 30% of cubic phase observed by the Rietveld method. 
                         Conclusion The Toraya equation showed an overestimated result of 
                         monoclinic quantification compared to the Rietveld method. 
                         Clinical significance The overestimated result of monoclinic phase 
                         could lead to different interpretation about the dental Y-TZP 
                         ageing process.",
                  doi = "10.1016/j.jdent.2014.08.010",
                  url = "http://dx.doi.org/10.1016/j.jdent.2014.08.010",
                 issn = "0300-5712 and 1879-176X",
                label = "scopus 2014-11 ArataCaMaLaUsLiTa:2014:CrEv",
             language = "en",
        urlaccessdate = "04 dez. 2020"
}


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