Many patients experience temporary hair loss. The hair loss just behind the hairline is caused by a decreased blood supply. The decreased blood supply is caused by the incision itself cutting off the blood supply from the front and the tension created by lowering the hairline. After about 1 month, hair loss is at its maximum. The blood vessels spreading across the scar will create a new blood supply from the front and as the tissues relax, the tension will decrease. This will eventually result in hair regrowth. The extent and duration of this will vary from patient to patient, but generally most of the hair loss will be back after 6 months. If you want to do something about it, you can use some Minoxidil lotion. You can start using Minoxidil after the incision wounds have healed properly, three to four weeks after surgery.