Teeth and microbes
Importance of teeth
When you sit in front of a camera, the cameraman says 'cheese' and you 'smile'. What happens when you smile ? When you smile, your teeth become visible. If you have white shining teeth, it can make your smile beautiful. But just think, if you have yellow dusty teeth, would you feel comfortable in smiling ?
Clean white shining teeth add charm and beauty to our face. Teeth also give proper shape to our face and help us to speak properly. Teeth also help to chew and eat food properly.
Have you seen a person without teeth ? He/she looks different from a person having teeth.
His/her speech is not clear. our teeth not only give us a better look but also help us to speak clearly.
There are two sets of teeth:
- Milk teeth
- Permanent teeth
When a child is born, he does not have any teeth. But when the child is about 5-6 months old, the first set of teeth starts growing. They are called milk teeth. When the child is about 2 and 1/2 years old, he has total 20 milk teeth. These are also called temporary teeth because they do not last long. They are small in size. Slowly, they start falling out one by one. When the child is six years old, he loses all his teeth milk and they are replaced by a new set of bigger teeth called permanent teeth.
There are 32 permanent teeth : 16 in upper jaw and 16 in lower jaw. They are bigger than the milk teeth.
Parts of tooth
We have different types of teeth. But all of them have the same structure. Each teeth has two main parts:
Crown is the part of the tooth which is visible and root is the part which is present inside the gum. Gums hold the teeth tightly to their place.
The visible part of a tooth is called crown. It is covered with a hard layer called enamel. Enamel is the hardest substance in our body. Below the enamel lies the dentine. It is not as hard as enamel. Inside the dentine is a soft part called pulp. It has nerves and blood vessels.
These nerves send signals to brain when we have toothache. A long root fixes the tooth in the jaw.
Parts of tooth
Kinds of teeth
There are four kinds of permanent teeth. They are :
- Incisors- 8
- Canines- 4
- Premolars- 8
- Molars - 12
Kinds of teeth
Incisors or cutting teeth
They are used for cutting and slicing the food. There are four front teeth in each jaw, so 8 incisors are there in all.
Canines or tearing teeth
Canines are sharp and are used for tearing the food. there are 4 canines. Two canines are in the upper jaw and two in the lower jaw.
There are total 8 premolars, four in each jaw. they are broad teeth, next to canines. They help to crack the food and chew it properly.
There are 12 molars. They are present next to premolars. 3 molars on both sides in each jaw. They are bigger, flatter and broader and help to grind and crush the food.
Herbivores have well-developed premolars and molars as they have to chew the food and grind their food.
Name of teeth
Cutting and biting
Tearing the food.
Cracking and chewing the food
Grinding and chewing the food
Care of teeth
You know the teeth are very important for us. So, we must take care of our teeth. To keep them healthy and to prevent tooth decay, we must follow the following tips:
- We should brush our teeth in the morning and at night before going to bed.
- We should not eat too many sweets and chocolates. They spoil the teeth.
- We should rinse our mouth after every meal.
- Massage our gums every day to make them strong.
- To keep our teeth and gums strong, we must eat raw fruits and vegetables like radish, carrot, apple etc.
- Teeth are made of calcium. Milk, cheese, etc., are a rich source of calcium.
Care of teeth
When we eat, bites of food gets stuck between our teeth and can become breeding ground for germs. These germs form a thin sticky layer called plaque on teeth. This plaque can produce an acid which then starts dissolving the enamel and tooth decay starts.
Tooth decay causes holes in the tooth and foul smell in the mouth and stomach disorders. We can have toothaches too.
So, eat healthy food to keep your teeth healthy and don't forget to visit your dentist once in six months.
How to brush
- Regular brushing of teeth is the best way to keep the teeth healthy.
- Brush your upper teeth with down motion and lower teeth with upward motion.
- Brush out of the back of the teeth.
- Brush the flat surface of the premolars and molars.
How to brush
Microbes are tiny living organisms which cannot be seen with the naked eyes. They can be seen with the help of a microscope only. They are present everywhere. Microbes can be harmful as well as useful. Disease-causing microbes are called germs.
There are four kind of microbes:
- Bacteria may be rod-shaped, round or spiral. Some are harmful and cause diseases like typhoid, diphtheria, tuberculosis, etc. Some are useful as they break down the bodies of dead animals and plants into minerals.
- Viruses are smaller than bacteria. They cause diseases like common cold, polio, flu, mumps, etc.
- Protozoa are bigger than bacteria and cause diseases like malaria and dysentery.
- Fungi grow on dead plants and cause diseases like ringworm. Dandruff in hair is also caused by fungi. Some fungi are used in making bread, cake and beer.
Diseases caused by microbes
Points to remember
- We have two sets of teeth- Milk teeth and permanent teeth.
- Teeth help us to chew the food and help us to speak properly. They give shape to our face and add to the beauty of our face.
- There are four kinds of teeth- Incisors, canines, premolars and molars.
- A child has 20 milk teeth but an adult has 32 permanent teeth.
- We must take proper care of our teeth to keep them strong and healthy.
- Microbes are tiny living organisms. They are of four types- Bacteria, virus, protozoa and fungi.