Linda Tiley, ago 13, of Cleveland, Ohio, for her question:
What makes teeth decay?
Your second teeth are mount to last a lifetime and, with proper care, they probably will. Teeth in good condition hove been found in the skulls of human skeletons dug up after many hundreds of years. For tooth are made of dentine, which is harder than bone, and coated with enamel, the hardest substance in the human body.
In spite of this our teeth decay. They get cavities and rot away. And my, how a decaying tooth can hurt: While we live and eat and talk and breathe our tooth are always open to attack. The enemy is a host of assorted bacteria. These mites may measure as many Us 25,000 to an inch. They are too small for our eyes to see, yet they are everywhere ‑ in the air, the water and in our food. We cannot escape thorn.
Not all bacteria are our enemies. Most do us neither harm nor good. A few ire friendly. Our bodies could not function without the help of certain bacteria. Colonies of those allies live in our mouths and intestines and help us digest our food. The criminal element in the bacteria world runs about one in 30,000. Among these delinquents are the bacteria who attack our pearly teeth.
There are always colonies of bacteria in the mouth. Now varieties arrive overt' day. Some of these fellows are content to live on scraps of food. Others lodge in the crevices of the tooth and eventually devour tooth enamel. They, too, begin by outing scraps of food. Little flake's of tartar start to occur around the gum line of the tooth. This stuff is composed chiefly of living bacteria.
If allowed to remain, the tartar spreads. The hungry enemy begins to food on tooth enamel. The tooth begins to decay. A cavity develops which soon makes a hole in the softer dentine. The tooth jumps with pain whore you cat hot soup or cold ice cream. This is because the nerve in the center of the tooth has lost sum of its protection.
At this point you either visit the dentist or the bacteria dig deeper and deeper and deeper into the tooth. Soon the poor nerve has exposed end a throbbing toothache goes on day end night. If you leave it this long the dentist may be unable to save the tooth.
The bacteria which cause tooth decay are always present and always attacking. There is no way to leap them out. All vale can cl‑;, is defend. ourselves. This means brushing at least once a day. Use toothpaste and a soft brush so as not to scrape the enamel. But toothpaste and brush are not enough to keep the enemy at bay. Tartar forms at the base of the tooth even if you brush and. polish three times a day.
Luckily for us, bacteria are tiny mites. It takes several months to built sizeable flakes of tartar around the teeth. AIhEn this hGlnpCDs, off we go to the dentist to have our teeth cleaned. He scrapes off the tartar with spatial instruments. So, if you want your pearly teeth to last a lifetime, make a date with the dentist twice a year.
That way the little bacteria have less chance to cause decay and cavities. If the enamel is thin or broken, the dentist will spot the area and seal it up for you. This treatment does not hurt if you catch it before a deep cavity occurs.