Comparison the Effects of Different Root Canal Irrigants on the Retention of Quarts Fiber Posts Cemented by Resin Cement

Root canal irrigants could change the structure of root dentin and affect the posts retention the purpose of this study was to compare the effects of three different endodontic irrigants on the retention of quarts fiber posts cemented by different resin cement. In this in-vitro study, 10 mm long post spaces were prepared in root canals of 120 premolars after endodontic therapy and cutting the crowns at the cementoenamel junction. The teeth were randomly divided into four equal groups based on the irrigants as follows: distilled water, 2% chlorhexidine, 0.25% iodine and 1% NaOCl. Quarts fiber posts were cemented by Panavia F2. Samples were stored at 370c and humidity of 100% for one week. After thermocycling, the retention of fiber posts were measured by tensile test and modes of failure were reported. Data were analyzed by One-Way ANOVA, Tukey and Fisher's exact tests. The mean and standard deviation of the posts retention were 367.08±63.07, 377.59±72.02, 363.11±68.53 and 342.89±74.94 for distilled water, chlorhexidine 2%, iodine 0.25% and sodium hypochlorite, respectively. One-way ANOVA showed that there was a significant difference among the groups (P<0.001). The results of Tukey test showed that posts retention was significantly higher after rinsing by chlorhexidine (P<0.01) According to the results of this study, chlorhexidine rinse had a favorable effect on retention of posts cemented by resin cement.