Average time is 6 weeks to 3 months. But you can always have them removed by the surgeon if superficial. If you are asking about the deep sutures than time will allow the body to resorb them or phagocytize them. From MIAMI Dr. B
Dissolvable stitches dissolve anywhere from 30days to several months. Non-dissolvable ones will permanently remain. Skin stitches I do not use, just staples which I remove usually within several days to prevent stitch marks.