Comparison of Fiber Post Bond Strength to Root Canal Dentin Following Chlorhexidine and Carbodiimide Pretreatment

Background: Fiber post placement is a common practice for restoring endodontically treated teeth with weakened roots. The use of matrix metalloproteinase (MMP) inhibitors has been suggested to enhance the bond strength between fiber posts and root canal dentin. This study aimed to compare the push-out bond strength of fiber posts after root canal pretreatment with chlorhexidine and carbodiimide.Methods and Materials: Forty-five intact extracted, human single-rooted teeth (incisors, canines, and premolars) were collected. All specimens were similar in terms of root length and diameter. Teeth were sectioned from the cementoenamel junction (CEJ). The roots were instrumented using the crown-down technique and obturated using the lateral condensation technique. The post space was prepared by removing root canal filling materials with Gates Glidden drills and Peeso reamers. Specimens were randomly divided into three equal groups according to the applied surface pretreatment technique (n=15): 1) control: no pretreatment, 2) pretreatment with chlorhexidine %2 for 60 seconds, 3) pretreatment with carbodiimide 0.3 M for 60 seconds. Fiber posts were cemented into the canals using a self-adhesive resin cement)DMG - PermaCem2.0 (. Push-out bond strength of the specimens was assessed using a universal testing machine. Bond strength values were compared between the groups using the Kruskal-Wallis test. P-value<0.05 was considered statistically significant.Results: The push-out bond strength of the chlorhexidine and carbodiimide groups was 2.72 ± 1.86 MPa and 4.91 ± 6.17 MPa, respectively. No statistically significant differences were observed between the push-out bond strength values of fiber posts to root canal dentin in different pretreatment groups (P=0.33).Conclusion: Pretreatment of root canal surfaces with carbodiimide or chlorhexidine did not significantly affect the immediate push-out bond strength of fiber posts to root canal dentin.