The aim of this study is to evaluate the bond strength of AH Plus sealer after irrigation of the root canals using of Nano-Silver and Sodium hypochlorite. Sixty, freshly extracted, sound maxillary anterior teeth with completely formed apices and straight roots were used in this study. Each tooth was decoronated to provide approximately 16 mm± 1 of root, root canals with initial apical file size #20 were selected to approximately standardize the canal diameter. The samples were divided into two groups 30 root each according to the irrigation protocol used through instrumentation: Group A: root canal preparation was performed using the Protaper Next system during instrumentation the root canals were irrigated using Nano-Silver irrigant 0.02mol/L = 2000ppm. Group B: root canal preparation was also performed using the Protaper Next system but during instrumentation the root canals were irrigated using Sodium Hypochlorite (NaOCl) irrigant 5.25%.
Root canals of each group were then obturated using master cones of #40/06 and AH Plus sealer in lateral condensation technique. 2mm thick slices of apical, middle and coronal root portion for all samples were prepared for assessment of push out bond strength for the two groups.
Results showed that AH plus sealer had a lower value of push out bond strength ( 1.223± 0.533) in the group irrigated using nano silver than the second group irrigated with sodium hypochlorite (2.321 ± 0.650) at the coronal third with statistically significant difference( P= 0.004), also at the middle third it showed a lower value (1.732 ± 0.899) than the sodium hypochlorite but with no statistically significant difference, and finally at the apical third it also a lower value of push out bond strength (2.103 ± 1.319) than the other group irrigated with NaOCl (5.045 ± 1.397) with statistically significant difference (0.001)