I just know that I had horrible dry scalp for several years and my hair also started falling out really bad during that time.I finally found 2 products that got rid of my dry scalp and my hair quit falling out.Nizoral and Nioxin. Nizoral helped with my dry scalp but Nioxin helps with both.Hope this helps.

Thanks for reply, candycake. I purchased Paul Mitchell's Tea Tree shampoo and the tea tree hair and scalp treatment from my salon. So far my scalp feels refreshed and healthy. My hairdresser told me my scalp was very dry, I was just curious to know if the scalp was cured of dryness if the thin hair will grow back to thick. Have you ever heard of tea tree for dry scalp and thin hair? I hope it helps me.