Methods: 80 human extracted upper central incisors were endodontically treated. The coronal aspect were removed, They were divided into 3 experimental and 1 control groups (n=20). Roots were restored with 1 of following post systems: carbon fiber (C-Posts), quartz (Aestheti-Plus), glass fiber (FibreKor). A single bond adhesive (OptiBond Solo Plus) was applied, and light cured for 10 seconds. A dual-polymerizing resin luting agent (Variolink II) was used. Titanium ParaPost XT posts (control) were cemented conventionally using (Panavia 21) cement. Specimens were stored in light-proof boxes for 24 hours. Each root was cut horizontally, and three 1-mm-thick root segments (1 apical, 1middle, and 1 cervical) were prepared. Using a push-out test, the bond strength between post and dentin was measured using a universal testing machine. The data were analyzed with 2-way analysis of variance and Tukey’s Honestly Significant Difference test (α= 0.05).
Results: Post type and post space region resulted in significant differences for push-out bond strength (P<.001). Glass fiber posts (FibreKor) had significantly higher mean bond strength values (SD) for all post space regions. The carbon fiber posts (C-Posts) had significantly lower bond strength values at all post space regions. Quartz posts (Aestheti-Plus) and titanium posts (Parapost XT) groups had intermediate bond strengths, with no statistically significant differences among them. In addition, there were differences in bond strength among root thirds, with a reduction in values from the coronal to middle and apical thirds for all experimental groups (p<0.001).
Conclusions: Bond strength to root canal dentin varied with type of fiber reinforced composite post system used and region of root canal. Highest bond strength values were in coronal thirds and with glass fibers post systems.
Keywords: Dentin bonding agents, Prosthodontics, Root and Teeth
See more of: Dental Materials 9: Other Materials - Chemistry, Properties and Performance