Effect of laser heat treatment on Pull-out bond strength of fiber posts treated with different silanes

This study evaluated the effect of three different silanes and post-silanization treatments on the retentive strength of fiber posts luted with an etch-and-rinse resin cement.

One hundred intact maxillary central incisors were randomly divided into 10 groups after endodontic treatment and post space preparation (n=10). The fiber posts were etched using 24% hydrogen peroxide. Posts of the control group did not receive silane. In nine experimental groups, each of the three silanes used, Scotchbond Universal adhesive, Bis-Silane and Porcelain Primer, was subjected to three treatments: air-drying at 25°C, warm air-drying and CO2 laser heat treatment. After cementation of the treated posts using One-Step Plus/Duo-Link cement, the specimens were stored for one weak and then subjected to pull-out bond strength (PBS) testing. The data in Newton (N) were analyzed using two-way ANOVA and Tukey tests (α=0.05).

PBS was significantly affected by silane type and post-silanization treatment (p<0.001). The interaction of the two factors was not statistically significant (p=0.15). The effect of Porcelain Primer on PBS was significantly higher than those of universal adhesive (p<0.001) and Bis-Silane (p=0.01), with similar results for the two latter. Warm air-drying and laser treatment significantly increased PBS (p<0.001). The lowest and highest PBS was obtained in the control (no silane) group (190.9±31) and laser-treated/ Porcelain Primer group (377.1±50), respectively.

Warm air-drying and CO2 laser heat treatment had a significantly beneficial effect on retentive strength of fiber posts. Porcelain Primer was significantly more effective than universal adhesive and Bis-Silane. Key words:Laser heat treatment, Pull-out bond strength, fiber post.