Smoking has a distinctive and lasting impact on oral health in some interesting and alarming ways. The fact that cigarette smoking will kill one in five people from smoking-related illnesses, some of them pretty nasty, should be a big heads up [source: CDC]. That number -- one in five -- might be understating the smoking mortality stats in ways we'll get to in a second, however.

Your mouth is an interesting spot from which to explore the effects of smoking. Consider it the location where the poison from cigarettes hits the palate and gains access to the rest of you. Because what you smoke passes over your teeth and through your gums, your mouth is nicotine central -- in a very bad way. Destroying your appearance with nicotine-stained teeth and making your breath smell foul are just the superficial aspects of what smoking does to your oral health.

Periodontal disease is a group of disorders that affect the gums. In a healthy mouth, the gums stay snug up around the base of the teeth, providing protection to the roots. Smoking irritates gum tissue and reduces blood flow to the gums, causing damage that can result in the gums pulling away from the teeth [source: Inland Empire Perio].

Smoking may account for around 75 percent of periodontal disease (gum disease) experienced by adults. If you smoke, you have a seven times greater chance of developing periodontal disease than a nonsmoker [source: CDC]. Even if you're not a smoker but are exposed to secondhand smoke, you may be at risk for smoke-related periodontal disease [source: Perio.org].

One of the first and most noticeable indicators of periodontal disease is receding gums. Gum recession exposes the roots of teeth, leaving them vulnerable to tooth decay. This can be exacerbated by the loosening of the gums themselves, which form pockets below and between teeth that trap decaying food particles. Bacteria inside the mouth nestle into the pockets to feed on decaying food and create localized infections. Before that happens, though, the exposed roots of affected teeth become sensitive to hot or cold and may cause severe enough discomfort to warrant a trip to the dentist -- or at least a few dietary changes (as in no hot beverages or frozen treats) [source: ADA].

As the gums continue to deteriorate, bacterial growth leads to bad breath, cavities, mouth sores, infections and the rampant plaque growth. Plaque is the whitish, slimy film that develops on your teeth when you don't brush.

If plaque remains in the mouth long enough, it contributes to the development of biofilm, a destructive bacterial coating on teeth that resists brushing. Eventually, plaque hardens into tartar, a hard, cementlike layer around the gums and between teeth. Tartar makes the gum situation worse, causing additional irritation, bleeding and pain.

That's not all. Smoking can cause bone loss in the jaw, inflammation of the salivary glands and delayed healing from oral and other surgeries. Smokers are also more prone to oral cancers than nonsmokers [source: ADA].

There's something else to consider, too. In recent years, researchers have begun to see a correlation between oral health and whole body health. Although studies are ongoing, there's likely a connection between poor oral health and infections, inflammation and other problems throughout the body. Heart disease, rheumatoid arthritis, respiratory infections and some cancers may be linked to bacteria introduced through the mouth. If these statistical links are correct, the implications for smokers may be even more far-reaching than current illness and mortality statistics indicate [source: American Academy of Periodontology].