@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 = "27 abr. 2024"
}