Like most dental diseases, gum disease is a progressive condition. The infection is limited to the gums in the initial stages. If left untreated, it gradually spreads to the bones supporting teeth and starts eroding them. Eventually, the teeth lose their vital bone support and begin shaking. In this stage, you may experience difficulty in performing simple tasks like chewing due to the loose teeth, and also suffer from persistent bad breath. The earlier the treatment is sought, the lesser the damage done.