Abstract:

BACKGROUND: Fiber posts are currently perceived as promising alternatives to cast metal posts, as their elastic modulus are similar to that of dentin, producing a favorable stress distribution and providing more esthetic outcomes for endodontically treated teeth. Failure of a fiber post and composite resin core often occurs at the junction between the two materials. This failure process requires better characterization.
OBJECTIVE: To compare the bond strength of fiber posts after three surface treatments to a composite resin.
METHODS: The coronal portions of 20 mandibular premolars with a single root canal were removed and were endodontically treated. After post space preparation, the roots were divided into four groups and the fiber posts and resin cores were lured. In the three testing groups, the surfaces of fiber posts were silaned, sandblasted or etched with hydrogen peroxide. In the control group, the surfaces of fiber posts were not treated. All specimens were exposed to cyclic loadings and thermal cycles. The roots were sectioned into slices with 1 mm thickness and their bond strengths were tested with a universal material testing machine. Test piece following testing was placed under optical microscope to observe the breakage method.
RESULTS AND CONCLUSION: Stickiness strength was significantly greater in the sandblasted and hydrogen peroxide groups compared with the control group (P < 0.05). No significant difference in stickiness strength was determined between the sandblasted and hydrogen peroxide groups (P > 0.05). No significant difference in stickiness strength was detected between the silaned and control groups (P > 0.05). The splicing destruction among each group was the main breakage method between materials and fiber posts. The surface treatment of fiber posts with sandblast or hydrogen peroxide significantly enhanced the bond strength of the composite resin tested. The surface treatment of fiber posts with silane did not enhance the bond strength of the composite resin.