It is common practice to have sutures from surgery or a laceration repair removed after 7 to 10 days, if one has stitches of the non-dissolveable type. But the main reason that external sutures are removed is to prevent a type of scarring known as tracking or railroad marks, not because the wound is actually healed very well. The outermost layer of the skin, known as the epithelium, bridges or joins back together quite quickly in a week or so. But the deeper layers of the wound have not joined back together by even three weeks after surgery, having about 10% of normal tissue strength. This is why plastic surgeons place deeper sutures on the underside of the skin which is where the real support in suture repair is created. These internal dissolveable sutures take months to break down, giving the wound plenty of time to knit together and develop more normal tissue strength.