I have really bad dandruff, and my favorite boar bristle brush over the years has just been filled with hair and skin flakes. When I tried to brush dandruff off my scalp, I realized that from what was falling, I no longer knew if it was coming from my head or the brush. I also have one of those hat bracers for cleaning them. I found the gentlest way to clean the hat was to put it in the dishwasher with mild detergent. I figured why not try the hairbrush as well? The brush came out dandruff free! It was like getting a brand-new brush. There was still a little bit of hair in between the bristles, but it was so much better. I have rather short hair, so if you have long hair and don't want to have to dig it out of the dishwasher filter I would recommend using a comb to get as much as you can out, maybe also in conjunction with scissors like you would use on a vacuum cleaners roller brush.