Adhesion of a new methacrylate resin-based sealer to human dentin

The purpose of this study was to compare the shear bond strength of four root canal sealers: Fibrefill (a methacrylate resin sealer), Endion (a glass ionomer sealer), Topseal (an epoxy resin sealer), and CRCS (a calcium hydroxide sealer) to human root canal dentin. The dentin specimens were divided into four groups of 12 specimens each and etched with 3 ml of EDTA 17% before rinsing with NaOCl 2.5% and distilled water. Bond strength was tested using a test machine by subjecting samples to a shear load at a cross-head speed of 0.5 mm/min. The best results were observed in the Fibrefill group, in which the mean shear bond strength was 7.993 +/- 2.365 MPa. The values in the Endion (1.816 +/- 0.614 MPa) and CRCS (2.224 +/- 0.509 MPa) groups were significantly lower than in the Fibrefill and Topseal (6.235 +/- 1.428 MPa) groups. Inspection of the fractured surfaces revealed the bond failure to be mainly adhesive to dentin for Fibrefill and cohesive for Endion sealer. CRCS and Topseal sealers showed both adhesive and cohesive failures.