How long does one need to wear the sponge padding under the compression garment after lipo?

That is up to your surgeon. While in the last 25 years of practice I have not found that the sponge makes much/any difference in the long term result, I would not criticize using it. Depending on circumstances it may well help reduce irregularities from fibrosis. In MY opinion because the vast majority of meaningful swelling is typically gone by the end of the third week, it seems to me that three weeks would be plenty compared to any perceived benefit of using it longer.

Thank you for the question. I typically ask patients to wear the topifoam pads (sponge padding) for approximately 2 weeks post op. The topifoam pads help to splint the skin holding it in place during the initial healing.If after removal one notices irregularities forming, I ask the patient to continue to wear them for another 2 weeks thereafter. Best wishes.