Abstract: A temporary root canal sealer dispersion having a pH of at least 9 and comprising: (i) an aqueous dispersion medium comprising an oligomer and/or polymer having Lewis basic groups, and optionally a hydroxide of an alkali metal and/or a hydroxide of an alkaline earth metal, and (ii) a dispersed phase comprising a radio-opaque filler, wherein the weight ratio of oligomer and/or polymer having Lewis basic groups to hydroxide of an alkali metal and/or hydroxide of an alkaline earth metal is at least 0.5 when said aqueous dispersion medium comprises a hydroxide of an alkali metal and/or a hydroxide of an alkaline earth metal.

Abstract: A method of venting during sealing the cartridge. The cartridge body has an external wall, a generally cylindrical internal chamber wall having an internal chamber wall diameter and enclosing a cartridge chamber, and at least one channel wall forming a channel (or groove) in the chamber wall. The piston has a generally cylindrical plug wall positioned adjacent to the generally cylindrical internal chamber wall. The cylindrical plug wall has a diameter substantially equal to the diameter of the cylindrical internal chamber wall. Dental material is conveyed into the cartridge chamber. The piston is pressed into the cartridge chamber while venting gas from the cartridge chamber through the channel prior to forming a hermetic seal around the dental material in the cartridge chamber.