Surface porosity of hand-mixed, syringe-mixed and encapsulated set endodontic sealers

Objective: The objective of this study was to investigate the surface porosity of hand-mixed, syringe-mixed and encapsulated set endodontic sealers using image analysis. Study design: Eight different root canal sealers (AD Seal/Meta Biomed; AH Plus/Dentsply; MM Seal/Micromega; AH Plus Jet/Dentsply; EndoREZ/Ultradent; Epiphany/Pentron; GuttaFlow/Coltne; RealSeal/Sybron Endo) were prepared in accordance with the manufacturer's recommendations and dispensed into plastic rings (n = 10/group). Following set of the specimens, scanning electron photomicrographs of the sealer surfaces were taken at standard magnification. The area fraction and the minimum-maximum diameters of surface pores were calculated on the micrographs using ImageJ open-source image analysis software. Statistical comparisons were made between the sealers with respect to the area fractions and number of pores (Kruskal-Wallis test, P <.05). Results: The endodontic sealers differed significantly in both the percentage of area fraction and pore count (P <.001). The surface porosity of the methacrylate-based sealers Epiphany and RealSeal were significantly lower than those of resin-and silicone-based sealers. With the exception of AD Seal, hand-mixed sealers displayed significantly higher surface porosity than those of syringe-mixed ones (P <.001). The encapsulated sealer GuttaFlow exhibited the highest surface area fraction of pores. Conclusion: The mixing method influences the surface porosity of set endodontic sealers.