Zirconia changes after grinding and regeneration firing
Autor(a) principal: | |
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Data de Publicação: | 2017 |
Outros Autores: | , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da UNESP |
Texto Completo: | http://dx.doi.org/10.1016/j.prosdent.2016.09.026 http://hdl.handle.net/11449/163042 |
Resumo: | Statement of problem. Despite improvements in computer-aided design and computer-aided manufacturing (CAD-CAM) systems, grinding during either laboratory procedures or clinical adjustments is often needed to modify the shape of 3 mol(%) yttria-tetragonal zirconia polycrystal (3Y-TZP) restorations. However, the best way to achieve adjustment is unclear. Purpose. The purpose of this in vitro study was to evaluate the microstructural and crystallographic phase changes, flexural strength, and Weibull modulus of a 3Y-TZP zirconia after grinding with or without water cooling and regeneration firing. Material and methods. Ninety-six bar-shaped specimens were obtained and divided as follows: as-sintered, control; as-sintered with regeneration firing; grinding without water cooling; grinding and regeneration firing with water cooling; and grinding and regeneration firing. Grinding (0.3 mm) was performed with a 150-m diamond rotary instrument in a high-speed handpiece. For regeneration firing, the specimens were annealed at 1000 degrees C for 30 minutes. The crystalline phases were evaluated by using x-ray powder diffraction. A 4-point bending test was conducted (10 kN; 0.5 mm/min). The Weibull modulus was used to analyze strength reliability. The microstructure was analyzed by scanning electron microscopy. Data from the flexural strength test were evaluated using the Kruskal-Wallis and Dunn tests (alpha=.05). Results. Tetragonal-to-monoclinic phase transformation was identified in the ground specimens; R regeneration firing groups showed only the tetragonal phase. The median flexural strength of as-sintered specimens was 642.0; 699.3 MPa for as-sintered specimens with regeneration firing; 770.1 MPa for grinding and water-cooled specimens; 727.3 MPa for specimens produced using water-cooled grinding and regeneration firing; 859.9 MPa for those produced by grinding; and 764.6 for those produced by grinding and regeneration firing; with statistically higher values for the ground groups. The regenerative firing did not affect the flexural strength. Weibull modulus values ranged from 5.3 to 12.4. The SEM images showed semicircular cracks after grinding. Conclusions. Adjustments by grinding in 3Y-TZP frameworks should be performed with water cooling, and regeneration firing should be undertaken to obtain a more reliable material. |
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Repositório Institucional da UNESP |
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Zirconia changes after grinding and regeneration firingStatement of problem. Despite improvements in computer-aided design and computer-aided manufacturing (CAD-CAM) systems, grinding during either laboratory procedures or clinical adjustments is often needed to modify the shape of 3 mol(%) yttria-tetragonal zirconia polycrystal (3Y-TZP) restorations. However, the best way to achieve adjustment is unclear. Purpose. The purpose of this in vitro study was to evaluate the microstructural and crystallographic phase changes, flexural strength, and Weibull modulus of a 3Y-TZP zirconia after grinding with or without water cooling and regeneration firing. Material and methods. Ninety-six bar-shaped specimens were obtained and divided as follows: as-sintered, control; as-sintered with regeneration firing; grinding without water cooling; grinding and regeneration firing with water cooling; and grinding and regeneration firing. Grinding (0.3 mm) was performed with a 150-m diamond rotary instrument in a high-speed handpiece. For regeneration firing, the specimens were annealed at 1000 degrees C for 30 minutes. The crystalline phases were evaluated by using x-ray powder diffraction. A 4-point bending test was conducted (10 kN; 0.5 mm/min). The Weibull modulus was used to analyze strength reliability. The microstructure was analyzed by scanning electron microscopy. Data from the flexural strength test were evaluated using the Kruskal-Wallis and Dunn tests (alpha=.05). Results. Tetragonal-to-monoclinic phase transformation was identified in the ground specimens; R regeneration firing groups showed only the tetragonal phase. The median flexural strength of as-sintered specimens was 642.0; 699.3 MPa for as-sintered specimens with regeneration firing; 770.1 MPa for grinding and water-cooled specimens; 727.3 MPa for specimens produced using water-cooled grinding and regeneration firing; 859.9 MPa for those produced by grinding; and 764.6 for those produced by grinding and regeneration firing; with statistically higher values for the ground groups. The regenerative firing did not affect the flexural strength. Weibull modulus values ranged from 5.3 to 12.4. The SEM images showed semicircular cracks after grinding. Conclusions. Adjustments by grinding in 3Y-TZP frameworks should be performed with water cooling, and regeneration firing should be undertaken to obtain a more reliable material.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Sao Paulo State Univ, Araraquara Dent Sch, Dept Dent Mat & Prosthodont, Sao Paulo, BrazilSao Paulo State Univ, Araraquara Dent Sch, Dept Dent Mat & Prosthodont, Sao Paulo, BrazilFAPESP: 2011/11509-6Elsevier B.V.Universidade Estadual Paulista (Unesp)Hatanaka, Gabriel R. [UNESP]Polli, Gabriela S. [UNESP]Fais, Laiza M. G. [UNESP]Reis, Jose Mauricio dos S. N. [UNESP]Pinelli, Ligia A. P. [UNESP]2018-11-26T17:39:52Z2018-11-26T17:39:52Z2017-07-01info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/article61-68application/pdfhttp://dx.doi.org/10.1016/j.prosdent.2016.09.026Journal Of Prosthetic Dentistry. New York: Mosby-elsevier, v. 118, n. 1, p. 61-68, 2017.0022-3913http://hdl.handle.net/11449/16304210.1016/j.prosdent.2016.09.026WOS:000406079900011WOS000406079900011.pdfWOS000406079900011.pdfWeb of Sciencereponame:Repositório Institucional da UNESPinstname:Universidade Estadual Paulista (UNESP)instacron:UNESPengJournal Of Prosthetic Dentistry1,087info:eu-repo/semantics/openAccess2024-01-17T06:29:18Zoai:repositorio.unesp.br:11449/163042Repositório InstitucionalPUBhttp://repositorio.unesp.br/oai/requestopendoar:29462024-01-17T06:29:18Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP)false |
dc.title.none.fl_str_mv |
Zirconia changes after grinding and regeneration firing |
title |
Zirconia changes after grinding and regeneration firing |
spellingShingle |
Zirconia changes after grinding and regeneration firing Hatanaka, Gabriel R. [UNESP] |
title_short |
Zirconia changes after grinding and regeneration firing |
title_full |
Zirconia changes after grinding and regeneration firing |
title_fullStr |
Zirconia changes after grinding and regeneration firing |
title_full_unstemmed |
Zirconia changes after grinding and regeneration firing |
title_sort |
Zirconia changes after grinding and regeneration firing |
author |
Hatanaka, Gabriel R. [UNESP] |
author_facet |
Hatanaka, Gabriel R. [UNESP] Polli, Gabriela S. [UNESP] Fais, Laiza M. G. [UNESP] Reis, Jose Mauricio dos S. N. [UNESP] Pinelli, Ligia A. P. [UNESP] |
author_role |
author |
author2 |
Polli, Gabriela S. [UNESP] Fais, Laiza M. G. [UNESP] Reis, Jose Mauricio dos S. N. [UNESP] Pinelli, Ligia A. P. [UNESP] |
author2_role |
author author author author |
dc.contributor.none.fl_str_mv |
Universidade Estadual Paulista (Unesp) |
dc.contributor.author.fl_str_mv |
Hatanaka, Gabriel R. [UNESP] Polli, Gabriela S. [UNESP] Fais, Laiza M. G. [UNESP] Reis, Jose Mauricio dos S. N. [UNESP] Pinelli, Ligia A. P. [UNESP] |
description |
Statement of problem. Despite improvements in computer-aided design and computer-aided manufacturing (CAD-CAM) systems, grinding during either laboratory procedures or clinical adjustments is often needed to modify the shape of 3 mol(%) yttria-tetragonal zirconia polycrystal (3Y-TZP) restorations. However, the best way to achieve adjustment is unclear. Purpose. The purpose of this in vitro study was to evaluate the microstructural and crystallographic phase changes, flexural strength, and Weibull modulus of a 3Y-TZP zirconia after grinding with or without water cooling and regeneration firing. Material and methods. Ninety-six bar-shaped specimens were obtained and divided as follows: as-sintered, control; as-sintered with regeneration firing; grinding without water cooling; grinding and regeneration firing with water cooling; and grinding and regeneration firing. Grinding (0.3 mm) was performed with a 150-m diamond rotary instrument in a high-speed handpiece. For regeneration firing, the specimens were annealed at 1000 degrees C for 30 minutes. The crystalline phases were evaluated by using x-ray powder diffraction. A 4-point bending test was conducted (10 kN; 0.5 mm/min). The Weibull modulus was used to analyze strength reliability. The microstructure was analyzed by scanning electron microscopy. Data from the flexural strength test were evaluated using the Kruskal-Wallis and Dunn tests (alpha=.05). Results. Tetragonal-to-monoclinic phase transformation was identified in the ground specimens; R regeneration firing groups showed only the tetragonal phase. The median flexural strength of as-sintered specimens was 642.0; 699.3 MPa for as-sintered specimens with regeneration firing; 770.1 MPa for grinding and water-cooled specimens; 727.3 MPa for specimens produced using water-cooled grinding and regeneration firing; 859.9 MPa for those produced by grinding; and 764.6 for those produced by grinding and regeneration firing; with statistically higher values for the ground groups. The regenerative firing did not affect the flexural strength. Weibull modulus values ranged from 5.3 to 12.4. The SEM images showed semicircular cracks after grinding. Conclusions. Adjustments by grinding in 3Y-TZP frameworks should be performed with water cooling, and regeneration firing should be undertaken to obtain a more reliable material. |
publishDate |
2017 |
dc.date.none.fl_str_mv |
2017-07-01 2018-11-26T17:39:52Z 2018-11-26T17:39:52Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://dx.doi.org/10.1016/j.prosdent.2016.09.026 Journal Of Prosthetic Dentistry. New York: Mosby-elsevier, v. 118, n. 1, p. 61-68, 2017. 0022-3913 http://hdl.handle.net/11449/163042 10.1016/j.prosdent.2016.09.026 WOS:000406079900011 WOS000406079900011.pdf WOS000406079900011.pdf |
url |
http://dx.doi.org/10.1016/j.prosdent.2016.09.026 http://hdl.handle.net/11449/163042 |
identifier_str_mv |
Journal Of Prosthetic Dentistry. New York: Mosby-elsevier, v. 118, n. 1, p. 61-68, 2017. 0022-3913 10.1016/j.prosdent.2016.09.026 WOS:000406079900011 WOS000406079900011.pdf |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Journal Of Prosthetic Dentistry 1,087 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
61-68 application/pdf |
dc.publisher.none.fl_str_mv |
Elsevier B.V. |
publisher.none.fl_str_mv |
Elsevier B.V. |
dc.source.none.fl_str_mv |
Web of Science reponame:Repositório Institucional da UNESP instname:Universidade Estadual Paulista (UNESP) instacron:UNESP |
instname_str |
Universidade Estadual Paulista (UNESP) |
instacron_str |
UNESP |
institution |
UNESP |
reponame_str |
Repositório Institucional da UNESP |
collection |
Repositório Institucional da UNESP |
repository.name.fl_str_mv |
Repositório Institucional da UNESP - Universidade Estadual Paulista (UNESP) |
repository.mail.fl_str_mv |
|
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1803650285779812352 |