RESUMEN
Aim: The aim of this in-vitro study was to investigate the effects of MTAD (a mixture of doxycycline, citric acid, and a detergent) on the bond strength of AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) and EndoSequence BC sealer (Brasseler USA, Savannah, Georgia, USA). Materials & Methods: Eighty-four decoronated single-rooted human incisor teeth were prepared with Reciproc R25 files (VDW, Munich, Germany), and the canal was irrigated with 5 mL 1.3% NaOCl. The roots were randomly assigned to four groups (n = 21), according to the final irrigation protocol and sealer selection: Group 1: distilled water-AH Plus; Group 2: distilled water-EndoSequence BC; Group 3: MTAD-AH Plus; Group 4: MTAD-EndoSequence BC. For the final flush, in Groups 1 and 2, the root canals were irrigated with 5mL of distilled water; in Groups 3 and 4, 5mL of MTAD was used for 1 minute. After root canal obturation, specimens was embedded in an acrylic block and sectioned horizontally at three levels (coronal, middle, apical). Bond strength of sealer to root canal dentin was assessed via push-out test using a universal testing machine. Results: There were no significant differences among the groups in coronal and apical thirds. In the middle root third, Group 4 showed significantly lower push-out bond strength values than Group 2 (p=0.023). No significant difference was found between the two root canal sealers. Conclusions: Overall, MTAD final irrigation caused lower push-out bond strenght values than distilled water with no significancy.