Influence of Cement Insertion Technique on Fiber Post Bond Strength

Objective: this study evaluated the influence of different methods of resin cement insertion on the bond strength between bovine root dentine and fiber posts (null hypothesis: the insertion methods do not influence the bond strength). Methods: forty bovine roots (16mm) (single-root) were prepared to 12 mm with custom drill of the fiber post system (FRC Postec Plus). The roots were embedded in chemically cured acrylic resin using a surveyor. The specimens were divided into 4 groups, according to the methods of resin cement insertion: G1- Lentulo drill, G2- Centrix syringe, G3- Explorer #5, G4- with the aid of the Post. The root canals were rinsed with 20 mL of distilled water, and dried with paper points. The root dentine was etched with H2PO3 37%/15s + washing/drying and the adhesive system AllBond 2 was applied, and right away the cylinder quartz fiber posts (Aestheti-Plus) were cemented (RelyX). The samples were kept in distilled water 37⁰ C for 24 h, then, each specimen was cut into 4 slices of ±1.8 mm of thickness, and the samples were submitted to push-out test (Emic DL-1000) (1mm/min). Results: ANOVA (a=0.05) showed that the bond strength (MPa) was not affected by resin cement insertion methods (P>0.05). G1 (4.21±1.27a), G2 (3.17±1.79a), G3 (4.46±0.95a), G4 (3.12±1.28a), (null hypothesis was accepted). Conclusion: the resin bond strength between the bovine root dentin and the fiber posts are not influenced by the resin cement insertion methods.