Adapter for drill driven lavage system with first fastener for connecting the adapter to a drill drive, and second fastener for connecting the lavage system to the adapter. A shaft supported to rotate in axial direction and to connect to the drill drive that the shaft can be rotated by the drill drive. The adapter comprises a disc which is connected to the shaft in such manner that the disc rotates along when the shaft rotates. The disc comprises an attachment in an eccentric arrangement or the disc is inclined towards the rotation axis of the shaft. The adapter is connected to the lavage system by second fastener so that the rotating disc drives the lavage system. The adapter is connected to the lavage system by means of the second fastening facility in such manner that the pestle drives the lavage system and hits periodically onto a membrane of the lavage system.
