Microtensile bond strength between resin cements and composite cores submitted to different surface treatments

• Grant number: 13/16167-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2013
• End date: November 30, 2015
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Paulo Henrique dos Santos
• Grantee: Jaqueline Barros de Rossi
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

The objective of this study is to evaluate the microtensile bond strength of resin cements to composite cores submitted to different surface treatments, at 24 hours and 6 months after the bonding procedure. Fifty-six blocks of Filtek Z250 composite resin will be prepared and divided into 4 groups according to the surface treatments: Group 1 (control), without any surface treatment; Group 2 37% phosphoric acid during 30 seconds; Group 3: 37%phosphoric acid + silane during 60 seconds; Group 4: 37% phosphoric acid + Adper Single Bond 2. Two resin cements will be used for bonding of Tescera indirect composite to the blocks of Filtek Z250 resin composite, a conventional resin cement, RelyX ARC, and a self-adhesive resin cement, RelyX U200. The samples will be stored in distilled water at 37 º C for 24 hours and subsequently sectioned into sticks measuring approximately 1.0 x 1.0 mm. Half of samples will be used to evaluate the microtensile bond strength, while the other half will be stored for 6 months in artificial saliva, pH neutral at 37. C, changed weekly. The surfaces involved in the fracture of each specimen will be analyzed in scanning electron microscopy for classification of the fracture pattern and subsequently subjected to statistical tests to verify the significance of the data (± = 0,05).