There are many factors that go in to a decision about reconstruction after Mohs surgery or excision of a skin cancer on the nose. The convex areas such as the nasl tip or the convex surface of the nostril in those patients whose nostrils are very rounded, do not typically heal well with just dressing changes. The concave areas of the crease around the nostril heal somewhat better, or the area between the nasal bridge and the eye in its concavity. If a patient's skin is very thick and has oily porous skin, the second intent healing may leave too shiny and thin a scar to match. Skin grafts are not a perfect match, either, however. In fact, over a year, the graft becomes thinner and yellow or even brown on rare occasions whereas others become white. Some wounds that are left to heal on their own contract and leave a disfigured appearance of a close-by cosmetic area if it is pulled from the conraction. For these reasons, a flap is often done, in which the neighboring skin maintains its blood flow and texture and color but creates a larger scar than second intent healing or a graft. Reconstruction possibilities are numerous and require a physician to think of your anatomy, skin characteristics, neighboring regions with their "free margins" that can get pulled because they have nothing anchoring them, etc. Science and art is involved in this decision making process, mixed with experience.