The aim of this study was to determine whether using a silane-containing universal adhesive as a silane primer in glass-ceramic/resin cement systems affects biaxial flexural strength (BFS) and bonded interface integrity after loading. Glass-ceramic (IPSe.max CAD, Ivoclar/Vivadent, Schaan,...

The aim of this study was to determine whether using a silane-containing universal adhesive as a silane primer in glass-ceramic/resin cement systems affects biaxial flexural strength (BFS) and bonded interface integrity after loading. Glass-ceramic (IPSe.max CAD, Ivoclar/Vivadent, Schaan, Liechtenstein) disc-shaped specimens (6.5 +/- 0.1mm in diameter, 0.5 +/- 0.1mm thick) were etched with 5% hydrofluoric acid (HF) for 20 seconds and divided into four groups of 30 specimens, to be treated as follows: 1) One bottle silane primer (RCP); 2) Separate application of silane and adhesive (RCP+SB); 3) Silane-containing universal adhesive (SBU); 4) No treatment (C). After silanization, all specimens were resin cement- coated and polymerized for 40 seconds. Each specimen layer was measured, as well as each assembly's thickness, using a digital caliper and scanning electron microscope (SEM). Specimens were stored for 24 hours and submitted to a BFS test (1.27 mm/min). BFS values were calculated using the bilayer disc-specimen solution. Bonded interfaces were analyzed on fractured fragments using SEM. Oneway ANOVA and Tukey tests (alpha=0.05) were applied, as well as the Weibull analysis. Factor "silane treatment'' was statistically significant (p<0.0001). RCP+SB (372.2 +/- 29.4 MPa) and RCP (364.2 +/- 29.5 MPa) produced significantly higher BFS than did the C (320.7 +/- 36.3 MPa) or SBU (338.0 +/- 27.1 MPa) groups. No differences were found in the Weibull modulus (m: RCP: 10.117.3; RCP+SB: 10.1-17.0; SBU: 12.3-22.4; C: 7.4-12.9). Bonded interface analysis exhibited ceramic-cement separation (SBU, C) and voids within the resin cement layer (all groups). Neither the ceramic/cement system's BFS nor its bonded interface stability were improved by SBU after loading.

CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ

310650/2013-5

COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES

Fechado