The effects of non-thermal plasma and conventional treatments on the bond strength of fiber posts to resin cement

OBJECTIVES: This study compared the effect of hexamethyldisiloxane (HMDSO) and ammonia (NH(3)) plasmas on the bond strength of resin cement to fiber posts with conventional treatments. MATERIALS AND METHODS: Sixty-five fiber posts were divided into 5 groups: Control (no surface treatment); H(2)O(2) (24% hydrogen peroxide for 1 min); Blasting (blasting with aluminum oxide for 30 sec); NH(3) (NH(3) plasma treatment for 3 min); HMDSO (HMDSO plasma treatment for 15 min). After the treatments, the Ambar adhesive (FGM Dental Products) was applied to the post surface (n = 10). The fiber post was inserted into a silicon matrix that was filled with the conventional resin cement Allcem Core (FGM). Afterwards, the post/cement specimens were cut into discs and subjected to a push-out bond strength (POBS) test. Additionally, 3 posts in each group were evaluated using scanning electron microscopy. The POBS data were analyzed by one-way analysis of variance and the Tukey's honest significant difference post hoc test (α = 0.05). RESULTS: The Blasting and NH(3) groups showed the highest POBS values. The HMDSO group showed intermediate POBS values, whereas the Control and H(2)O(2) groups showed the lowest POBS values. CONCLUSION: Blasting and NH(3) plasma treatments were associated with stronger bonding of the conventional resin cement Allcem to fiber posts, in a procedure in which the Ambar adhesive was used.