The hairline scar will be irregularly curved for a natural effect. It will be red and clearly visible at first, but after about 6 weeks it will become less noticeable and the hairs will start to grow through the fine scar. The scar will mature for about a year. Will the scar be visible? This defends the density of the hair just behind the hairline. With dense hair, the scar will be barely visible once the hair roots that have been pushed under the scar have grown through the scar. If the hair is thin, the scar may become visible when you pull the hair back.