Impact of different surface treatment methods on bond strength between fiber post and composite core material

Abstract

Purpose To assess the impact of different surface treatments on the push-out bond strength between fiber post and a composite resin core material. Material and methods Seventy-two glass-fiber posts were randomly assigned into six groups according to the method of surface treatment: Control (no treatment), silane, sandblasting, hydrofluoric acid, hydrogen peroxide, and hydrogen peroxide with sandblasting. Two posts from each group were inspected under a scanning electron microscope to assess the surface modifications and 10 posts were employed for the push-out test. Each post was placed vertically in the middle of a cylindrical putty matrix and a dual-cure composite resin material was applied for core build-up. Two discs of each specimen were cut using a low-speed diamond saw (total 120 discs). The push-out test was executed using a universal testing machine at a crosshead speed of 0.5 mm/min. Statistical analysis was performed using one-way ANOVA and Tukey’s test ( p ≤ 0.05). The mode of failure of each disc was evaluated under SEM. Results The sandblasting and hydrofluoric acid groups presented significantly higher bond strength than control and hydrogen peroxide groups. The hydrogen peroxide groups exhibited significantly the lowest bond strength of all groups. There was no significant difference between the control and silane groups. All groups showed predominantly adhesive failure except the hydrogen peroxide with sandblasting, where the cohesive failure of the post was predominant. Conclusions Sandblasting and hydrofluoric acid surface treatments demonstrated superior results to silane and hydrogen peroxide. The combined method of hydrogen peroxide and sandblasting could weaken the fiber post and lead to clinical fractures.

Effect of Glass Fiber Post Surface Treatment on Bond Strength of a Self-Adhesive Resin Cement: An “In Vitro” Study

“…We observed greater BS in the cervical region of the root canal than in other regions. These results agree with the work of Alshahrani et al [ 17 ], in which the RelyX U200 cement showed higher BS values in the cervical third, regardless of the type of surface treatment of the post. The success of adhesive cementation inside the root canal, mainly at the apical level, can be compromised by several factors.…”

“…Researchers disagree about the actual benefit of silanization in improving GFP retention, and other surface treatment alternatives have been investigated [ 11 , 14 ]. The roughness produced on the post surface with mechanical ( e.g ., blasting) [ 14 , 16 ] or chemical ( e.g ., application of hydrogen peroxide) methods [ 16 , 17 ] has been shown to improve the retention of GFPs fixed with resin cement by removing the matrix layer of epoxy resin and increasing the area of contact with the fibers that will be silanized [ 18 , 19 ].…”

Effect of Luting Cement Film Thickness on the Pull-Out Bond Strength of Endodontic Post Systems

“…In previous studies, different methods, such as pull-out; push-out, and micro-tensile tests, have been used for the evaluation of the bond strength of posts cemented to natural tooth roots. The pull-out tensile bond strength testing of the cemented posts is considered superior to the other tests [ 17 , 18 , 19 ]. Previous studies have also used pull-out bond strength on natural teeth to clinically simulate the retention of endodontic post systems, and they have reported similar results [ 20 , 21 ].…”

“…These findings are similar to previous studies, which showed that the debonding of posts occurs when cement film thickness is increased [ 12 , 14 ]. It was proposed from the studies that when the cement layer is thinner, there will be less micro-porosities and polymerization stress, leading to higher retentive bond strength [ 14 , 18 ].…”

“…Coronal 2 mm of gutta-percha was removed with a gates glidden drill, and the access opening was sealed with temporary restorative material (Cavit, 3M ESPE, St. Paul, MN, USA) [ 17 ]. All the teeth were then stored in 100% relative humidity at room temperature [ 18 ]. After 24 h of obturation, the specimens were prepared for post space by using peeso reamers (Pulpdent Corp, Watertown, MA, USA) size 4 and 5 under copious water irrigation with a slow speed dental handpiece (NSK, Nakanishi Inc. Shinohinata, Japan) attached to a customized dental surveyor (J. M. Ney Co., Hartford, Connecticut, CT, USA) to guide post space preparation parallel to the long axis of the teeth ( Figure 2 ).…”