Influence of air abrasion and bonding agents on bond strength of interface zirconia/adhesive resin cement (Rely X U200))

• Grant number: 14/24074-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2015
• End date: January 31, 2016
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Renata Garcia Fonseca
• Grantee: Beatriz Aquino Pereira de Souza
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

A strong and stable union interface restoration / cement results in greater longevity of indirect restorations. Considering that the yttria stabilized zirconia by surface characteristic features unreceptive, different surface treatments and bonding agents have been proposed in the literature. Among these treatments, air abrasion is one of the most investigated and has as main objective to promote micromechanical retention. Regarding the bonding agent, its role is to establish chemical reactions that interface. However, the existing wide range of both particles employed in the compositions of air abrasion as bonding agents, as well as the different possibilities of combining them, in search of mechanical and chemical union, make the selection of these two factors difficult. The purpose of this study is to investigate the effect of different particles used in air abrasion and bonding agents on bond strength of zirconia / adhesive resin cement interface. Ninety-six discs (5.0 mm diameter x 2.0 mm thick) will be obtained from Lava zirconia (3M ESPE) and randomly divided into two groups (n = 48) according to the following conditions of air abrasion: 1) particles of aluminum oxide (Al2O3) 120 mm; 2) particles Al2O3de 120 mM + 110 mM Al2O3de particles modified by silica (Rocatec Plus - 3M ESPE). After air abrasion, the discs are cleaned with 99% isopropanol in ultrasound for 3 min and then receive one of the following treatments (n = 12): 1) no bonding agent (control group); 2) Clearfil SE Bond Primer / Clearfil Porcelain Bond Activator (Kuraray); 3) only Clearfil Porcelain Bond Activator; 4) RelyX Ceramic Primer (3M ESPE). Composite resin discs (5.0 mm diameter x 2.0 mm thickness) are cemented on the surface of zirconia treated with adhesive resin cement Rely X U200 (3M-ESPE). The specimens are thermally cycled (10,000 cycles - 5:55 ° C and immersion time of 30 s) and subjected to shear test in a mechanical testing machine (EMIC). The data will be statistically analyzed according to the results of normality and homoscedasticity (± = 0.05) tests. After the shear test, the fracture mode of the specimens will be examined with a stereomicroscope (20x).