(PR049) The Effect of Sealer Type and Cementation Timing on the Fiber Post Pull Out Strength

Objectives: The present study aimed to evaluate the effect of two types of endodontic sealers—a newly developed calcium silicate-based bioceramic sealer (One-Fil MDCLUS Co.,LTD) and a conventional epoxy resin-based sealer (Ribbon,Dentsply/Sirona)— and the timing of post cementation on the retention strength of fiber posts. The null hypothesis was neither the sealer type nor the cementation time affect the pull-out-bond-strength of the fiber posts.

Methods: Sixty intact maxillary central incisors were sectioned at the cementoenamel junction. The teeth were mounted in acrylic resin, cleaned, and shaped with hand and rotary files. The samples were randomly divided into four groups: R-I: obturation with Ribbon sealer and immediate post cementation; BC-I: obturation with One-Fil sealer and immediate post cementation; R-1W: obturation with Ribbon sealer, post cementation after 1 week, and BC-1W: obturation with One-Fil, post cementation after 1 week. Fiber posts (Unicore size-3,Ultradent), the Prelude(Zest-Dental) bonding system, and Anchore(Vista-Apex) core-build-up resin composite were used for post cementation. Pull-out tests were conducted 1 hour after post cementation using an Instron-Universal-Testing machine at 1mm/min cross head speed. Data were analyzed using two-way ANOVA at a 0.05 confidence interval.

Results: The mean values for each group (in kgf) were as follows: R-I: 15.9(±6.3); BC-I: 15.4(±8.0); R-1W: 13.2(±5.82); BC-1W: 10.8(±5.6). No statistically significant difference was found among sealers (p=0.410) but the immediate groups had significantly higher pull-out-bond-strength than the 1 week group (p=0.041).

Conclusions: Pull-out-bond-strength in endodontically treated teeth is significantly higher at the day of obturation/post cementation compared to the post-placement one week later.