[Effects of sealing of dentinal tubules of root canal wall with Ag (NH3)2F (3.8%) solution].

In this study, in order to determine a method for obtaining a good reaction, the reactive products of 3.8% Ag (NH3)2F, using formalin as a reducing agent, were studied. Saforide RC was used as the 3.8% Ag (NH3)2F solution and 10% neutral formalinsolution was used as a reducing agent. The silver mirror test and reaction products on the root canal wall were investigated under the scanning electron microscope, along with observation of dye penetration using a stereoscopic microscope. Reaction of periapical tissue to the materials was studied histologically in dogs. In the natural reduction group, less amounts of reactive products were seen, and sealing of the dentinal tubules of the root canal wall was inadequate. In the formalin reduction group, large amounts of reactive products were found, and the dentinal tubules of the root canal wall were sealed. CaF2, Ag3PO4, Ag2O and Ag were identified as reactive products. In the natural production groups, obstruction was present but incomplete. In Formalin groups, dye osmosis obstruction was recognized. No harmful action of the solution on the surrounding tissue of the dog's tooth was recognized.