Don't denoise, level and then clean the rest of the dirt specks and grains using either the paintbrush or dodging and burning. It means a bit more effort, but, you get a far better end result. When people use denoise on tank scans it just shows laziness, it murders the greys and lowers the quality greatly.
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You can make two layers, one on top that is leveled enough to have good blacks and whites, and one on bottom that is leveled as much as possible without ruining the grays. Then put a layer mask on the top one and remove the gray areas using the brush or selecting the area and filling it in with black. Depending on the art style or page, you can do the reverse, and the one with good grays is on top, and the layer mask is to let the good whites and blacks show through from the layer underneath.
That method is only for when there's dust that actually can be leveled out, but doing so kills the grays. But additionally, there can be dust that no amount of leveling will remove, so you have to brush it out by hand like was mentioned already. Usually there's not too much of it per page, and sometimes the dust speck blends in with a line or a complicated area so it doesn't matter.