TEETH AND DECAY

AYSUDA PASİNLİOĞLU 214 ZELİHA REFAYELİ 217

TEETH• The hardest substances in the

body, the teeth are also necessary for chewing (or mastication) — the process by which we tear, cut, and grind food in preparation for swallowing. Chewing allows enzymes and lubricants released in the mouth to further digest food.

• What's the difference between "baby" teeth and permanent teeth? At between six and ten months of age, most infants begin to get their "baby" teeth.

• The Central Incisors (front middle teeth) usually come in first, and then teeth begin appearing on either side and work their way back to the second molars. By the time a child has reached three years old, most of the "baby" teeth should be present.

• The process begins to repeat itself when the child is about seven years old. The Central Incisors fall out first and are replaced by permanent teeth. By the ageof 21, most people have all of their permanent teeth.

• Fluoride is a natural element that can be found in many things, like the water we drink and the food we eat. Decades ago, scientists began to notice that children who lived in places where fluoride occurred naturally in the water, had fewer dental cavities.

• Fluoride that is absorbed by your body is used by the cells that build your teeth to make stronger enamel.

• A tooth is basically made up of two parts: the crown and the root.

• The crown is what you see when you smile or open your mouth. It's the part that sits above your gum line.

• The root is below the gum line. It makes up about 2/3rds of the tooth's total length.

• Four different tissues make up each tooth. The enamel is the durable, white covering. Enamel protects the tooth from the wear and tear of chewing.

Dental Fact: did you know that the enamel on your teeth is the hardest substance in your body?

• Dentin supports the enamel on your teeth. It's a yellow bone-like material that's softer than enamel and carries some of the nerve fibers that tell you when something is going wrong inside your tooth.

• The Pulp is the centre of the tooth. It's a soft tissue that contains blood and lymph vessels, and nerves. The pulp is how the tooth receives nourishment and transmits signals to your brain.

• Cement is what covers most of the root of the tooth. It helps to attach the tooth to the bones in your jaw. A cushioning layer called the Periodontal Ligament sits between the cement and the jawbone. It helps to connect the two.

What is tooth decay?Tooth decay is the process that results in

a cavity (dental caries). It occurs when bacteria in your mouth make acids that eat away at a tooth. If not treated, tooth decay can cause

pain, infection, and tooth loss.

SOURCES:

• http://www.healthyteeth.org/experiments/powerFlu.html

• http://www.healthyteeth.org/• http://www.google.com.tr/search?q=teeth&hl

=tr&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=7-8CT53hEKeQ4gT7trmNCA&ved=0CHYQsAQ&biw=1014&bih=623

•THANKS FOR LISTENING…