During a hair restoration, healthy donor hair is moved from the back of the patient’s head to the thinning areas.  In this case, Sam’s hair was all but gone.  He hid his thinning hair with the existing hair.  He chose High Density Hair Grafting (HD/HG), which is the best choice for large cases.  Once the DHT resistant hair is relocated, it will permanently grow as long as it would have grown in the back of his head.