An applicator for dental compounds includes a shaft, the front end of which can be connected with the aid of a fastening device to a syringe containing the dental compound, and a plunger. The shaft contains a ram for advancing the plunger. The fastening device has an inner sleeve, attached to the shaft, and an outer sleeve, attached on the inner sleeve rotatably with respect to it. The inner sleeve is substantially cylindrical and has such a cavity that its cross section is substantially U-shaped. Clamping takes place as a result of eccentricity.