http://www.oramd.com/recedinggums/2-gumsreceding.htm
It's not like there isn't enough to worry about in regards to oral hygiene without adding in the threat of receding gums. Thousands of people every year are diagnosed with this common dental threat. In order to have better control of your dental health, it is important to be aware of receding gums, what causes them, how to prevent it, and some steps to take to reduce the damage if it does happen to you.