Abstract: The invention relates to a trench cutter comprising a cutter frame, at least one rotatably drivable cutter wheel, which has cutting teeth on its outer circumference for removing ground material, at least one bearing shield, which is arranged on the underside of the cutter frame and is configured to support the at least one cutter wheel, at least one conveyor box, which has at least one opening for discharging removed ground material and/or for feeding a suspension and is arranged in the region of the at least one bearing shield, wherein the at least one cutter wheel has, on its side facing the bearing shield, at least one flap tooth which can be adjusted between an unfolded position, in which the flap tooth removes ground material below the bearing shield, and a folded position for running past at the bearing shield.