We've all done it - absent-mindedly touched a hot pan or put our hands too close to a grill. What's left is an ugly, painful red mark; a burn. While burns are pretty commonplace, they require a bit more care than a scratch or other skin injury. This is because burns can cause damage below the surface that you can't see. When heat or chemicals burn your skin, they not only deal damage in a way that you can visibly see, but the heat penetrates down through the layers of cells. This is why burns scar and tend to hurt...