Fracture Resistance of Endodontically Treated Teeth Restored with Fibre or Cast Posts

The purpose of this study was to determine the fracture resistance of 4 post and core systems. 40 extracted maxillary canines (for orthodontic reason) were used for this study. The samples were divided into 4 groups, which were: Group (1) Cast post luted with Rely X ARC; Group (2) Cast post cemented with zinc phosphate; Group (3) Fibre post luted with Rely X + Filtek Z-250 as core material; Group (4) Fibre post luted with Rely X + Vitremer Core Build Up as core material. The post cores were loaded (N) to fracture by a universal testing machine and data were analyzed (Oneway ANOVA). The obtained fracture resistance results were as follows: Gr 1 (2103.50 N ± 185.75) > Gr 2 (1494.80N ± 164.04) > Gr 3 (1004.90 N± 108.72) > Gr4 (739.40 N ± 96.93). Vertical root fractures were observed in the cast post-core groups. Hybrid composite cores in group 3 showed cohesive failures, whereas resin modified glass ionomer cores in group 4 showed a failure of adhesive nature from dentin.