Vickers hardness and fracture toughness of one feldsphatic ceramic veneer to zirconia core submitted to different cooling rates

• Grant number: 10/05395-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2010
• End date: June 30, 2012
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Gelson Luis Adabo
• Grantee: Natália Bertolo Domingues
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Yttrium oxide-stabilized tetragonal zirconia polycrystalline (3Y-TZP) was introduced in prosthetic dentistry at the end of the twentieth century to be used as all-ceramic fixed prostheses core. Despite its good mechanical properties, during sintering of venner ceramic, an inadequate cooling rate or a thermal mismatch between venner ceramic and 3Y-TZP can cause problems such as chipping and fracture of venner ceramic. It is suggested that an inadequate cooling rate can increase the residual stress and change the ceramic glass matrix causing failures in theses prostheses. The purpose of this project is to compare the Vickers hardness and fracture toughness of monolayer (only veneer) specimens under different cooling rates. (AU)