Comparasion of fracture strength of post-core systems used in post-endodontic restorations

Objective: The aim of this study was to compare the fracture strength of different post-core systems used in the restoration of endodontically treated teeth with excessive material loss. Materials and Methods: Forty-five single and straight-root decoronated human mandibular premolar teeth were used. After root canal treatment, post space preparation have been made. Teeth were randomly divided into three groups : Group 1 glass fiber post-composite core, Group 2 composite post-core, Group 3 lithium disilicate post-core. For all groups, fracture resistance (N) value was measured and recorded using a universal testing machine. The types of fractures in the teeth were examined. Bonferroni and Shapiro-Wilk tests were used for statistical analysis of the data. Results: As a result of the statistical evaluation of the results obtained, a statistically significant difference was found between the fracture strength values of the groups (p<0.05). The fracture strength of the teeth in the fiber post-composite core group was significantly lower than the other two groups, while there was no significant difference in fracture strength between the composite post-core and lithium disilicate post-core groups. Restorable fracture types were more common in the fiber post- composite core group, while unrestorable fracture types were more common in the composite post-core and lithium disilicate post-core groups. Conclusion: Within the limitations of this study, the fracture strength of the fiber post-composite core group was lower than the composite post-core and lithium disilicate post-core groups, and the fracture types in the fiber post-composite core group were more restorable. Keywords: Fiber post, Fracture resistance, Post-core