Teeth



Teeth are the first part of the digestive system. Their job is to begin the physical break down food by chewing and thereby sheering some of the tough connective tissue.

Anatomy
There are many parts that make up the tooth anatomy:

Enamel- the part of the tooth that everyone sees. It is the tough shiny white outer surface.



Cementum- a tough, yellowish bone like layer that covers the root of the tooth. The periodontal membrane is in this part of the tooth.

Periodontal membrane- fleshy tissue that is located between the tooth and tooth socket, and it is there to hold the tooth in the socket.

Dentin- the part of the tooth that is under the enamel and cementum. This part of the tooth is harder than bone but is also porous.

Pulp- the soft center of the tooth and it contains blood vessels and nerves. Its function is to bring nutrients to the Dentin.

Nerves- The nerves in the tooth do what most nerves do and that is convey messages to and from the brain.

Crown- the visible part of the tooth.

Root- the part of the tooth that imbeds itself into the jawbone. The number of roots will range from one to four.

Gums- the soft tissue that surrounds the base of the tooth.

Types



 * Incisor- These are the front teeth of humans. They have a flat edge and are used for cutting through food. A human Adult will have 8 incisors and each of them only have one root.


 * Canine- These teeth are also known as cuspid teeth. The word canine means of or like a dog. You have 4 of these teeth and they are used to hold and tear food. These teeth also only have one root.


 * Molars- These are the wide flat teeth found in the back of a mammals mouth. Humans have 12 molars and the ones in the top jaw have 3 roots and the ones in the lower jaw have 2 roots. They are used for chewing food.


 * Premolar- These teeth are also known as bicuspid because they have two points. They are located between the canines and molars. There are 8 of them and they only have one root.

Secondarily teeth can be defined as primary, permanent, and wisdom teeth.


 * Primary- Primary teeth are the first teeth that anyone gets, they are also called the baby teeth. There are 20 baby teeth that you will get. They don't start to become visible till you are about six months old. They will have been forming in you gums ever since you were born.


 * Permanent- The primary teeth eventually will fall out and will be replaced by 32 permanent teeth also known as adult teeth. Primary teeth will fall out from the age of 6-14. The formation of the permanent teeth will start in the jawbone right under the primary teeth. The roots of the primary teeth then dissolve and this causes the teeth to become loose and fall out. The permanent teeth then will take its place.


 * Wisdom- These teeth are molars and are also known as the third molars. They wont come in till you are 17-21.

Diseases
Tooth Decay: This happens after you eat and comes from the acid you get from sugar and starch. The acid will turn into plaque about 20 minutes after you eat and if the plaque doesn't get removed then it will turn into tartar. After awhile tartar will start eating away the enamel of the tooth and leave holes in it which is called tooth decay. Another word for this is cavities and that is the more common term. Tooth decay is up there in one of the most common diseases and the common cold is really the only one that beats it out.

Cavities are normally painless until they start to get deeper into the roots. Tartar will eat away at the tooth until you have to remove it if you don't remove it. If you do have tooth decay it is better if you get it looked sooner than later because it will be more painful and expensive if you wait. There are different ways that dentists can see if you have a cavity, that is they will pock it with a sharp object and if it is soft then that means there is a cavity. They also use x-rays to see if there are cavities because sometimes they aren't visible from the outside.

The way that dentists repair cavities is that they have to drill out the cavity and replace it with a substance. The most common fillers used is silver alloy, gold, porcelain, and composite resin. Dentists use porcelain and composite resin in the front teeth because it has a closer color of teeth but it is weaker so they put silver alloy and gold in the back teeth that aren't seen as much. Once the tooth has decayed so long that it has eaten most of the tooth it is to late to put a filler in so they have to drill out the rest of the cavity, also known as a root canal, and replace it with a crown. A crown basically takes the shape of the tooth and takes its place when the tooth is to decayed and weak by itself.

Gingivitis: This is when inflammation and infection affects the gums around the teeth. What causes the inflammation is plaque build up from sugar and starch. Another way that causes inflammation is overly vigorous brushing and flossing. People who have braces, bridges, dentures and crowns are more likely to get gingivitis then those without them.

The way a dentist knows if you have gingivitis is your gums will be reddish pink and have plaque at the base of the teeth. The gums may also be mildly tender but are usually painless. The way to treat this is to just clean your teeth often to remove the plaque. When you go to get a check up on you teeth a dentist will teach you how to do this.