Microtensile bond strength of adhesive systems to dentin with or without application of an intermediate flowable resin layer

Autor(es)

Mario Fernando De Goes ^[1] ; Marcelo Giannini ^[2] ; Vinícius Di Hipólito ^[3] ; Marcela Rocha de Oliveira Carrilho ^[4] ; Márcia Daronch ^[5] ; Frederick Allen Rueggeberg ^[6]

Afiliação do(s) autor(es)

^[1] State University of Campinas. School of Dentistry of Piracicaba. Department of Restorative Dentistry - Brasil

^[2] State University of Campinas. School of Dentistry of Piracicaba. Department of Restorative Dentistry - Brasil

^[3] State University of Campinas. School of Dentistry of Piracicaba. Department of Restorative Dentistry - Brasil

^[4] State University of Campinas. School of Dentistry of Piracicaba. Department of Restorative Dentistry - Brasil

^[5] Medical College of Georgia. School of Dentistry. Department of Oral Rehabilitation - Estados Unidos

^[6] Medical College of Georgia. School of Dentistry. Department of Oral Rehabilitation - Estados Unidos

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Dental Journal; v. 19, n. 1, p. 51-56, 2008-00-00.

Resumo

This study evaluated the effect of flowable composite resin application on the microtensile bond strength (muTBS) of adhesive systems to dentin. Occlusal surfaces of human third molars were ground to obtain flat dentin surfaces. The crown of each tooth was sectioned occluso-gingivally into four quarters with a water-cooled diamond saw. One of the following adhesive systems was applied to dentin surface in each quarter of the same tooth, following manufacturers' instructions: Scotchbond Multipurpose, Single Bond Adper Prompt and Clearfil SE Bond. Experimental and control groups received the same treatment, except for the fact that a layer of flowable composite (Filtek Flow) was placed and light-cured on top of the adhesive layer in the specimens of the experimental groups. Resin composite (Filtek Z250) crown buildups were then made on the bonded surfaces and incrementally light-cured for 20 s. The restored teeth were stored in water at 37ºC for 24 h. Each tooth quarter was serially cut in a longitudinal direction in order to obtain several bonded sticks (0.9-mm² in cross-section). Maximal microtensile stress (in MPa) at failure was recorded using a universal testing machine. Data were analyzed by two-way ANOVA and Tukey's test at 5% significance level. Placement of a low-viscosity resin to the hybridized dentin increased the muTBS for all tested adhesive systems. However, such increase was significant only for Clearfil SE Bond (p<0.05). When the restorations were placed without low-viscosity resin, Clearfil SE Bond presented higher muTBS than Adper Prompt (p<0.05). For the groups treated with flowable composite, Clearfil SE Bond produced the highest muTBS means to dentin. In conclusion, the effect of the addition of an intermediate flowable composite layer on muTBS to dentin was material-dependent and resulted in an increased adhesion for all tested materials, though with significance only for Clearfil SE Bond. (AU)

• Processo FAPESP: 03/08090-7 - Efeito da smear layer nos procedimentos adesivos com sistemas autocondicionantes.
• Beneficiário: Marcelo Giannini
• Modalidade de apoio: Auxílio à Pesquisa - Regular