Influence of thermomechanical fatigue on bond strength of repaired composites

Author(s)

da Silva, Bruno Rodrigues ^[1] ; Silva Sousa, Ana Beatriz ^[1] ; Ramos Salles de Oliveira, Dayane Carvalho ^[2] ; Martins Giamatei Contente, Marta Maria ^[1] ; Alandia-Roman, Carla Cecilia ^[1] ; Coelho Sinhoreti, Mario Alexandre ^[2] ; Panzeri Pires-de-Souza, Fernanda de Carvalho ^[1]

Affiliation

^[1] Univ Sao Paulo, Ribeirao Preto Sch Dent, Dept Dent Mat & Prosthodont, BR-14040904 Ribeirao Preto, SP - Brazil

^[2] Univ Estadual Campinas, Piracicaba Sch Dent, Dept Restorat Dent, BR-13414903 Piracicaba - Brazil

• Document type: Journal article
• Source: INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES; v. 61, p. 65-70, SEP 2015.
• Web of Science Citations: 1

Abstract

Objective: The aim of this study was to evaluate the influence of thermomechanical fatigue (TMF) and two adhesive systems on bond strength (BS) of repaired nanofilled composite. Materials and Methods: A hundred test specimens (8 mm diameter x 8 mm thickness) were obtained (Filtek Z350, 3M ESPE, St. Paul, MN, USA) and separated in 10 groups (n=10), according to the type of adhesive system for repair and TMF, after and before repair. Control groups: G1 - without repair and TMF (control); G2 - without repair+TMF. Groups repaired with total-etch adhesive system (ASB - Adper Scotchbond Multi-Purpose, 3M ESPE): G3 - repaired without TMF; G4 - TMF before repair; G5 - TMF after repair; G6 - TMF before and after repair. Groups repaired with self-etch adhesive system (CLB - Clearfil Liner bond 2V, Kuraray Dental): G7 - repaired without TMF; G8 -TMF before repair; G9 - TMF after repair; G10 - TMF before and after repair. After treatments, sticks (1 mm(2)) were obtained and submitted to the microtensile test (0.5 mm/mm). Failure modes were observed in Scanning Electron Microscopy (SEM-Jeol JSM 5600LV). Results: Statistical analysis (2-way ANOVA, Tukey, p <0.05) demonstrated that G2 presented highest BS values that differed statistically compared with those of other repaired groups submitted to TMF (p <0.05). Regarding control groups, G2 presented the highest BS values, different from Cl (p=0.0087). Fractographic analysis demonstrated that all repaired groups showed predominantly adhesive failures regardless of the adhesive system used. Conclusions: The TMF can improve the BS of repaired composites mainly when used self-etch adhesive, which demonstrated higher BS. The timing of TMF influences the BS of the repair on composite. (C) 2015 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 12/09397-8 - Effect of thermomechanical fatigue on bond strength of repaired composite
• Grantee: Bruno Rodrigues da Silva
• Support Opportunities: Scholarships in Brazil - Scientific Initiation