An applicator for a one-handed operation for storing and applying a dental liquid, including a container for the dental liquid and a tubing for guiding the dental liquid from the container to an applicator tip. The container is made of foil, which can be punctured by a mandrel. The dental liquid is expelled through a displacement plunger, whereby puncturing and expelling are effected through actuating a handle and the container is positioned with respect to the mandrel in suitable manner such that the advancing mechanism that is used to expel the dental liquid from the applicator is also used to puncture or slit open the foil with the mandrel, whereby the container is opened through the same force that is used to dispense the dental liquid and one-handed operability of the applicator is attained not only when the dental liquid is dispensed, but also when the container is being opened.
