A mouthpiece for a dental cleaning device comprises a supporting structure configured to encompass a plurality of teeth of a dental arch. The supporting structure has an inner surface facing a tooth surface. At least one brushing chamber is provided at the inner surface side. The brushing chamber comprises a flexible wall part being deformable by pressurizing or depressurizing the brushing chamber. Bristles extend externally from the flexible wall part. In a method of brushing teeth, a plurality of teeth is encompassed by the mouthpiece, and the at least one brushing chamber is alternatingly pressurized and depressurized.
