Evaluation of the influence of different sandblasting protocols on shear bond strength of a CoCr alloy and heat-activated acrylic

• Grant number: 11/03413-9
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2011
• End date: July 31, 2012
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Estevão Tomomitsu Kimpara
• Grantee: Estevão Tomomitsu Kimpara
• Host Institution: Faculdade de Odontologia (FOSJC). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil
• Associated researchers: Carolina da Silva Machado Martinelli

Abstract

This study will evaluate the influence of different air blasting protocols (procedures), bond agents and shear bond strength in a CoCr alloy and a heat-activated resin. For it, 528 metalworking cylinders will be made. The specimens will be divided in 24 groups (n=20), for the shear bond strength test, according to the factors: particle (Al2O3 - 50 and 110µm); pressure (2,5 and 6,0Atm); and the distance from the metal surface to microjets (10 and 20cm). The specimens will be cleaned and one specimen for each group will be analyzed in a rugosimeter and a scanning electron microscope (SEM) after the air blasting, what will be realized for 10s; and then the specimens will be subdivided and will be applied the following agents: metal primer (Alloy Primer, Kuraray CO, Ltda., Osaka, Japão); ceramic opaque (Vita VM®13, Wilcos do Brasil Indústria e Comércio Ltda, Petrópolis, RJ, Brazil); and their combined used. The specimens will be submitted to a short polymerization cycle. After cooling, the specimens will be deflasked, finished and polished, and posteriorly will be submitted a thermal cycle. The shear bond strength test will be realized and the results will be subjected to statistical analysis. After cracking, one specimen of each group will be analysed to SEM and DRX, and the fractures of the specimens will be analyzed in a stereomicroscope. (AU)