Fracture resistance comparison of TWO post systems in different intracanal lengths

Objective: The aim of the present study was to compare the fracture resistance of a glass fiber post core system and a recently introduced bundled fiber post core system in two different intracanal lengths. Method: In the present study, 40 human mandibular 1st premolar teeth with similar sizes were endodontically treated, distrubuted to four groups (n=10) and sectioned near the cemento enamel junction to have roots with 15 mm length. Group 1 consisted of endodontically treated teeth (ETT) restored with glass fiber posts in 5 mm intracanal length, Group 2 consisted of ETT restored with bundled fiber posts in 5 mm intracanal length, Group 3 consisted of ETT restored with glass fiber posts in 9 mm intracanal length and Group 4 consisted of ETT restored with bundled fiber posts in 9 mm intracanal length. After the core build up, specimens are covered with low viscosity silione and embedded in acrylic blocks. Specimens were then placed in a specifically designed apparatus for stabilization and subjected to compressive force at 450 angle until fracture occurs. Fracture values and fracture patterns were recorded. Statistical analysis was done using SPSS software. Results: There was no significant difference between the groups in regard of post length and type. (P>0.05) Restorable fractures were more common in all groups. Conclusion: Fiber posts can be used at shorter lengths in curved root canals that carry a risk of perforation. Bundled fiber post system have the same fracture resistance as the glass fiber post system.