Taking care of halitosis often means doing more than just brushing and flossing. After all, bad breath doesn't come solely from food particles and tooth decay - it can also be related to tobacco, alcohol, pungent foods, gingivitis, ulcers, postnasal drip and tonsil stones. The latter have been causing bad breath since as far back as medical history can recall.
Physicians have known about the tonsils for millennia. These glands are a part of the body's lymphatic system. They don't appear to do much, but during an infection the tonsils gather and store dead bacteria, which helps the body get through illness.
In the case of a severe infection - strep throat is a good example - the tonsils can swell severely and develop folds and channels, like a raisin. Tonsils that have this appearance are called "cryptic," and they are efficient manufacturers of tonsil stones.
Also called tonsilloliths, tonsils stones occur when food matter gets caught as it passes the tonsils on its way down the throat. Over time, these balls of food, collagen and bacteria grow larger, like a pearl. When they become large enough, people feel a discomfort in their throat and a need to hawk or spit repeatedly.
Tonsil stones also cause potent bad breath. Studies have shown that the surface of a tonsillolith is covered with a film of microbes, which give off copious amounts of volatile sulfur compounds, the molecules that give halitosis its scent.
Medieval doctors were certainly aware of tonsil stones. These growths could clue a surgeon in to the need for a tonsillectomy, for which the 10th-century Arabian surgeon Abulcasis developed a special tonsil guillotine, according to Strathern's A Brief History of Medicine.
One of the first modern mentions of tonsil stones appears in an 1800 issue of the Medical and Physical Journal, a publication of the Royal College of Physicians, London. Surgeon John Hewitt writes of "a case of calculous concretions in the tonsils" of a 39-year-old woman.
The patient had repeated throat infections, after which she had stones "of a light yellow colour, and about the size of a small field bean" stuck in her tonsils. Hewitt wrote that the stone "weighed 11 grains [0.7 grams], and was exactly of the form and colour that I sent it" - indicating that he mailed the putrid stone to a lucky Society member.
Today, most tonsil stones are relatively easy to deal with. By gargling with a specialty breath freshening rinse after meals, individuals with halitosis can dislodged tonsil stones, moisten the mouth and keep breath smelling fresh.