Interface Analysis of an Adhesive Sealer and Root Canal Dentin.

Abstract

It is generally accepted that creation of "hybrid layer" can seal dentin and prevent leakage. Therefore, when adhesive sealers are used for root canal treatment, it is expected that both coronal and apical leakages can be reduced. The purpose of these studies is to analyze a resin-dentin interface of root canal sealer (MetaSEAL, Parkell, Inc., U.S.A.) by instrumental analyses.
Using SEM a 10-20-micrometer layer was observed between root canal wall and resin sealer. It might be a resin-impregnated dentin layer because the layer had a structure of dentinal tubule. The EDS analysis showed that the Ca concentration of the layer was lower than normal dentin. The FT-IR analysis showed that the resin sealer component was detected in the layer.
From these analyses,it became clear the original root canal dentin surface layer had a low Ca concentration and a porous structure. Resin sealer had permeated into this layer and polymerized. This zone is considered a "hybrid layer".