Hair Regrow

Part of my scalp was sunny, as the hair is dead. At that time I did not know that the sun can kill your follicles. Now that I know, stay away from sunlight and grow longer hair to cover the scalp more. I was looking for a new follicular growth, but my hair seems thinner. Never enter the hair follicles that have been damaged by the sun? If no follicles then there is no possibility of hair growth. Sorry once you damage the hair follicles can not grow hair there.