Patricia Forsythe age 12, of Nashville Tenn
What makes a tooth decay?
Tooth decay is caused by tiny invaders$ too small for the eye to see. They were discovered soon after the microscope was invented about 300 years ago. Anthony Van Leeuwenhoek of Holland studied some of that crumbly tarter from a tooth under his lens. He was amazed to find it teeming with little wrigglers: Obviously they were very much alive„ So he called them animalcules ‑ meaning little animals ‑ which is what they are. The little creatures were renamed bacteria in 1838. Leeuwenhoek drew and described several of the various bacteria that cause tooth decay.
The world teems with bacteria, There are many varieties in our mouths. Most of them are neutral: A few are friendly and even aid in digestion. A few are bandits who claim squatters rights around our teeth and set up housekeeping at our expense. They dine on bits of foodo our food, Some are removed, or at any rate disturbed, when we brush our teeth, but not all of them. The rest thrive and multiply forming hard tartar at the base of our teeth.
It is this tartar that weakens the pearly enamel which coats our teeth. Tooth enamel is a hard substance, the hardest in the body.‑ But it cannot endure long when clogged with tartar. It wears thiniand begins to orack and chip. Sensible people let the dentist remove this tartar twice a year, Otherwise those bandit bacteria really dig themselves in.
Trouble starts when the enamel coat begins to wear. The tooth gives a warning signal ‑ a stab of pain when it is touched by hot soup or cold icecream. The dentist can re‑enforce the weak spot, if you get there in times If not, the happy bacteria move right through the hard enamel barricade to more comfortable living quarters. Inside is the boney dentine of which most of the tooth is made,
Dentine is hardy but much softer than outer enamel. It is fed by blood vessels coming up through the roots of the tooth which are embedded in the gums. And running up he center is a nerve. This is the nerve that warns of trouble when the enamel begins to wear thin.
When the bacteria set up housekeeping in the dentine that nerve really goes into action. Its warning signals are the horrible pain of toothache. This does not bother the bacteria. They go right on thriving and mulitiplying. The decay area grows and the cavity gets bigger day by day:
Things are now so bad that you just cannot stand it any longer. You creep along to the dentist and sit in that chair expecting the worst. The dentist peers and prods. Maybe we can save the tooth ‑ but it means a lot of drilling and filling. Once in a while the bacteria bandits have decayed too much of the tooth. Out it must come by the roots too late we realize that a little care may have kept it for us.