Abstract:
Purpose: The objective of this study was to investigate the effect of surface
treatments of three laboratory fabricated composites (SR Adoro, Belle glass NG and
GC Gradia) on their microtensile bond strength with the direct resin composite (Filtek
Z350).
Materials and methods: Four laboratory resin composite blocks of each
material were fabricated and polished to 600 grit. The specimens of each laboratory
resin composite were then randomly assigned into four groups and treated with one of
the following methods: Group1: no surface treatment (Control); Group2: sandblast
only (SA); Group3: silane only (SI); Group4: sandblast plus silane (SA+SI). Single
bond 2 adhesive was applied to the treated laboratory resin composite surfaces and
covered with direct resin composite (Filtek Z350). The direct resin compositelaboratory
resin composite blocks were cut with cutting machine producing bars
specimens (n=15), which were loaded to failure under tension in a microtensile tester.
The mean microtensile bond strength was analyzed with one-way ANOVA.
Results: Statistical analysis showed that the bond strength was significantly
affected by surface treatment for belleGlass NG and SR Adoro, but not GC Gradia.
For Adoro, group3 (SI) there were significantly lower bond strengths than group1,2,4
(p<.05). For bellGlass NG, group4 (SA+SI) there were significantly higher bond
strengths than other groups (p<.05). For no surface treatment and treatment with silane
only, GC Gradia showed significantly higher bond strengths than other materials
(p<.05).
Conclusion: Aluminum oxide sandblast followed by silane application
improved the bond strength for SR Adoro. GC Gradia had a higher microtensile bond
strength than belleGlass NG and SR Adoro when it had no surface treatment or had a
silane surface treatment only