10 nm and 1 mm a length l of the end side surface of the respective tooth flanks 19 c is preferably between 10 u03bcm and 1 mm the tooth crest face 19 d of the tooth 19 is configured in a planar manner in the present embodiment fig4 shows a view in longitudinal section of the internal gear pump in the mounted state according to the preferred embodiment of the disclosure the pinion 10 is preferably arranged eccentrically in the ring gear 12 and meshes with the latter the first axial plate 14 is arranged on a first end side of the pinion 10 and of the ring gear 12 the second axial plate 15 is arranged on a second end side of the pinion 10 and of the ring gear 12 the first axial plate 14 and the second axial plate 15 each bear in a sealing manner against the pinion 10 and the ring gear 12 fig5 shows a schematic illustration of the pinion of the internal gear pump according to a further preferred embodiment of the disclosure the pinion 10 preferably has the toothing 18 formed on an outer circumference of the pinion 10 a respective tooth 19 of.