The Effect of Root Canal Irrigation Solution on Flexural Strength of Dentin

Objectives: This study was to investigate the effect of a variety of root canal irrigation solutions on flexural strength of dentin. Materials and Methods: Fifty intact, extracted human mandibular third molars were used in this study. Each tooth was sectioned using diamond cutting disc to create dentin bar (1X1 mm, with 7 mm in length). All dentin bars were randomly assigned into 5 groups of 10 each. Group 1, dentin bars were immersed in 5% NaOCl; group 2, in 2.5% NaOCl; group 3, in 15% EDTA; group 4, in 0.2% chlorhexidine gluconate (CHX); and group 5, in saline (as control) respectively. Each group was immersed for 2 hours. Each dentin bar was subjected to a three-point bend using MTS Universal Testing Machine to test the flexural strength. Data were analyzed using one way Anova, followed by Tukey s test performed at the 0.05 level of significance. Results: All irrigation solution have an effect on the flexural strength (P 0.05). EDTA caused the greatest effect on dentin mechanical properties, which revealed the lowest flexural strength (100.64 ± 7.23). In contrast, 0.2% CHX generated the least influence on dentin mechanical properties, which demonstrated the greatest flexural strength (189.85 ± 6.44). Conclusion: Root canal irrigation solution can induce effect on flexural strength of dentin. Chlorhexidine gluconate demonstrates the best irrigation solution since it has a slight effect on dentin mechanical properties, particularly flexural strength.