Shear bond strength of AH-26 root canal sealer to dentine using three dentine bonding agents.

Objective: The purpose of the study was to compare the bond strength of AH-26 root canal sealer to human root canal dentine exposed to different intracanal medications both with and without the use of three bonding agents. The materials used were AH-26 sealer, two one-bottle bonding agents (Single Bond, Bond-1) and one self-etching bonding agent (Clearfill SE Bond).

Methods: The dentine substrate was obtained from single rooted human teeth. The dentine specimens were treated either with EDTA 15% or phosphoric acid 37% to achieve the removal of smear layer. The AH-26 sealer was placed on the dentine surfaces both with and without the use of the bonding agents. Bond strength was tested using a single plane shear test assembly.

Results: The SBS values were (MPa): Group A (EDTA-AH-26) 3.678+/-0.853, Group B (Phosphoric acid-AH-26) 3.470+/-0.834, Group C (EDTA-Single Bond-AH-26) 4.8+/-0.865, Group D (Phosphoric acid-Single Bond-AH-26) 5.043+/-1.022, Group E (EDTA-Bond 1-AH-26) 4.939+/-0.877, Group F (Phosphoric acid-Bond 1-AH-26) 5.101+/-1.117, Group G (Clearfill SE Bond-AH-26) 6.975+/-1.694. The use of dentine bonding agents improved significantly (p<0.05) the adhesion of AH-26 sealer with the root canal dentine. However, the best results were obtained with the self-etching system. Similar results were observed from the pretreatment of dentine either with phosphoric acid 35% or EDTA 15%.

Conclusions: The use of dentine bonding agents gave higher shear bond strengths of AH-26 sealer to human root canal dentine.