Surface treatments on quartz fiber post: influence on adhesion and flexural properties

To evaluate (1) the effect of various surface treatments to optimize post adhesion, and (2) if these surface treatments had any adverse effect on the overall mechanical and chemical properties of the posts.

Six experimental batches were set according to the nature of the surface treatments which were followed or not by post silanization. Post surface treatments were: control, chloroform (CHCl3) and sandblasting (sand) with Al2O3 50 microm. The silane (sil) used was Silane Coupling Agent Calibra. In all cases, a dual-cure bonding agent was applied Prime&Bond NT + Self Cure Activator. The Groups were: 1 (control), 2 (sil), 3 (CHCl3), 4 (CHCl3 + sil), 5 (sand), 6 (sand + sil). Following surface treatments, the posts were embedded in resin composite and the composite-post interfacial strength was investigated with a push-out test. Flexural and fatigue tests were performed to control the mechanical performances of the treated posts. Push-out data were analyzed using two-way ANOVA and Scheffé's multiple means comparisons test (alpha = 0.05). SEM observations revealed the topographical modifications induced by sandblasting and the solvent.

Sandblasting or surface treatment with chloroform increased the bond strength (P < 0.001). The best values were obtained with the combination of sandblasting followed by post silanization. The flexural properties were not modified by the surface treatments (P = 0.072) and all the posts reached 3,000,000 cycles without breaking.