Periodontal disease is the progressive infection and loss of bone from around your teeth. Periodontal disease starts as gingivitis, the swelling of the gum around your teeth, and left untreated can cause your teeth to drift apart and eventually become so loose that they need to be extracted.

Periodontal disease is caused by the same things that cause gingivitis-plaque and tartar, and food that is not cleaned out from between the teeth. The plaque begins to spread down the roots of the teeth and the gums get infected which causes damage to the bone and fibers (periodontal ligament) which support the teeth. As the disease advances the gums begin to pull away from the teeth, allowing more food and plaque to be trapped under them, causing more damage. In the very advanced stages of the disease the teeth become loose and shift around because of the widespread damage to the bone and ligaments holding the teeth in. Because of this your bite may shift and you may have difficulty chewing, your teeth may look "long" and if you wear a partial denture it may no longer fit

In the early and moderate stages of periodontal disease proper treatment can prevent further damage and save your teeth. As the disease advances, untreated, the chances of saving your teeth become much worse. If periodontal disease is never treated your teeth will eventually need to pulled and full dentures made.

Periodontal disease can also be caused by using smokeless tobacco (snuff). In the areas where the snuff is held against the cheek the tobacco and by-products cause irritation and infection of the gums. The gums begin to recede and periodontal disease affects the teeth in the area. The area is also highly prone to oral cancer.