Experimental and finite element study of residual thermal stresses in veneered Y-TZP structures

Autor(es)

Tanaka, Carina B. ^{[1, 2]} ; Harisha, Hossam ^[2] ; Baldassarri, Marta ^[2] ; Wolff, Mark S. ^[3] ; Tong, Hui ^[4] ; Meira, Josete B. C. ^[1] ; Zhang, Yu ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Dent, Dept Biomat & Oral Biol, Sao Paulo - Brazil

^[2] NYU, Coll Dent, Dept Biomat & Biomimet, 433 First Ave, Room 810, New York, NY 10010 - USA

^[3] NYU, Coll Dent, Dept Cariol & Comprehens Care, Predoctoral Clin Educ, 345 East 24th St, New York, NY 10010 - USA

^[4] Cent S Univ, Sch Met & Environm, Changsha 410083, Hunan - Peoples R China

• Tipo de documento: Artigo Científico
• Fonte: CERAMICS INTERNATIONAL; v. 42, n. 7, p. 9214-9221, MAY 15 2016.
• Citações Web of Science: 9

Resumo

The main complications of zirconia-based laminated systems are chipping and delamination of veneering porcelain, which has been found to be directly associated with the development of residual thermal stresses in the porcelain layer. This study investigates the effects of cooling rate and specimen geometry on the residual stress states in porcelain-veneered zirconia structures. Bilayers of three different shapes (bars, semi-cylindrical shells, and arch-cubic structures) with 1.5 mm and 0.7 mm thickness of dentin porcelain and zirconia framework, respectively, were subjected to two cooling protocols: slow cooling (SC) at 32 degrees C/min and extremely-slow cooling (XSC) at 2 degrees C/min. The residual thermal stresses were determined using the Vickers indentation method and validated by finite element analysis. The residual stress profiles were similar among geometries in the same cooling protocol. XSC groups presented significantly higher tensile stresses (p= 0.000), especially for curved interfaces. XSC is a time-consuming process that showed no beneficial effect regarding residual stresses compared to the manufacturer recommended slow cooling rate. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved. (AU)

• Processo FAPESP: 13/06988-8 - Lascamento de porcelana sobre zircônia: ensaio experimental e análise por elementos finitos
• Beneficiário: Josete Barbosa Cruz Meira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 12/17094-5 - Lascamento de porcelana sobre zircônia: ensaio experimental e análise por elementos finitos
• Beneficiário: Carina Baptiston Tanaka
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto