Evaluation of the Sealing Ability of a Dual-Cure Self-Adhesive Methacrylate Resin Sealer Using a Novel Bacterial Leakage Test Model

抄録

This study aimed to evaluate the ability of MetaSEAL Soft Paste, a root canal sealer that has demonstrated favorable sealing performance in dye penetration tests, to prevent bacterial leakage compared with conventional sealers using a novel bacterial leakage test model. MetaSEAL Soft Paste, a methacrylate-based resin sealer, was compared with widely used sealers, including a zinc oxide eugenol-based sealer (Canals), an epoxy resin-based sealer (AH Plus Jet), and a calcium hydroxide-based sealer (Dentalis NX). In the bacterial leakage tests, the mid-root portion of a bovine incisor was horizontally sectioned. The root canal, prepared using a diamond point, was filled with sealer, and the specimen was subsequently placed on a brain heart infusion (BHI) agar. Specimens with a filter paper disc containing Enterococcus faecalis were incubated until bacterial colonization was observed. The antibacterial properties of the sealers were evaluated using the agar diffusion test and the direct contact test. Stable results in the bacterial leakage test demonstrated that this novel model is effective in accurately evaluating the ability of sealers to prevent bacterial leakage. No significant difference was observed in the ability of MetaSEAL Soft Paste to prevent bacterial leakage compared with AH Plus Jet and Canals. In the direct contact test, MetaSEAL Soft Paste and Canals showed significantly fewer bacteria than AH Plus Jet (P < 0.01), indicating higher antibacterial activity. This study suggests that the sealing ability of MetaSEAL Soft Paste was not superior to AH Plus Jet in preventing bacterial leakage, in contrast to the dye penetration test results.