DEC plugs?
Dreads Hair and Scalp Health
Hey there! I had a similar issue when I would scratch my scalp, Iwould seem to get little white balls as well. I have fairly dry skin and I've noticed that since I have dreaded, 11 months ago, my scalp has been dryer than "normal". I work for a Naturopathic Doctor and asked him what this was all about. His reply was something like this: "clogged hair folicles is caused by sebum, which is an oily secretion made by the sebaceous glands in the skin...the sebum coats the follicles and when mixed with sweat and oils it causes a blockage in the pore...thus causing irritation and little white balls.." this can happen to those who have dry scalps or oily scalps. Hope this info helps. There are numerous ways to help with this issue, i would suggest looking into what scalp treatment is right for your skin type and go from there...hope this helps! 
namaste*