Teeth and their structure Class 4

Table of Content

  • Teeth
  • Sets of Teeth
  • Difference between Temporary teeth and Permanent teeth
  • Types of Teeth
  • Structure of a Tooth
  • Tooth Decay and Care
  • FAQs
  • Teeth

    Teeth are hard, calcified structures that are found in our mouths. They play an important role in helping us chew and break down our food, speak clearly, and maintain the structure of our faces.

    Sets of Teeth

    a) We actually have two sets of teeth in our lifetime. The first set is called "temporary teeth" or "milk teeth," and the second set is called "permanent teeth" or "adult teeth."
    b) Most people have 20 milk teeth, which start to come in when we are about six months old. These teeth are smaller and not as strong as adult teeth.
    c) Around the age of six, our baby teeth start falling out, and our permanent teeth begin to come in.
    d) We get a total of 32 permanent teeth, which are stronger and bigger than baby teeth. These teeth are meant to last us for the rest of our lives if we take good care of them.

    Diagram of sets of teeth

    Difference between Temporary teeth and Permanent teeth

    Feature Temporary Teeth Permanent Teeth
    Eruption Time Emerge between 6 months to 3 years Begin emerging around age 6
    Number 20 32
    Function Aid in chewing, speech, and alignment Responsible for lifelong chewing and speech
    Replacement Eventually shed as child grows Intended to last a lifetime
    Root Development Roots are shorter and less anchored Develop deeper and more anchored roots
    Size Smaller in size Larger and more robust
    Tooth Names Incisors, canines, molars Same categories but with additional premolars
    Color Whiter Slightly yellower due to thicker dentin
    Enamel Thickness Thinner Thicker
    Caring for Them Require diligent care as a foundation for permanent teeth Maintenance is important for lifelong oral health
    Importance for Alignment Act as placeholders for permanent teeth Permanent teeth align with the guidance of temporary teeth

    Types of Teeth

    There are four main types of teeth: incisors, canines, premolars, and molars.

    1. Incisors

    a) These are the sharp, flat teeth at the front of our mouths.
    b) We have four incisors on the top and four on the bottom.
    c) Incisors help us bite into our food.

    2. Canines

    a) These are the pointy teeth next to our incisors.
    b) We have two canines on the top and two on the bottom.
    c) Canines help us tear and grip our food.

    3. Premolars

    a) These are the flat teeth behind our canines.
    b) We have four premolars on the top and four on the bottom.
    c) Premolars help us crush and grind our food.

    4. Molars

    a) These are the big, flat teeth at the back of our mouths.
    b) We have six molars on the top and six on the bottom.
    c) Molars also help us crush and grind our food.

    Diagram of different types of teeth

    Structure of a Tooth

    A tooth has three main parts:

    1. Crown

    a) This is the part of the tooth that you can see in your mouth.
    b) It's the white, hard part that helps us chew.
    c) The crown is covered in a tough substance called enamel, which is the hardest material in our bodies.

    2. Dentin

    a) This is the layer beneath the enamel.
    b) Dentin is not as hard as enamel, but it's still strong.
    c) It gives the tooth its shape and supports the enamel.

    3. Root

    a) This is the part of the tooth that is hidden below the gumline.
    b) The root helps hold the tooth in place in the jawbone.

    Inside the tooth, there is a soft, living part called the pulp. The pulp contains blood vessels and nerves that keep the tooth healthy and alive.

    Diagram of classified structure of a tooth

    Tooth Decay and Care

    a) Tooth decay happens when the bacteria in our mouths combine with the sugars from the food we eat to create acids.
    b) These acids can damage the hard outer layer of our teeth called enamel and create tiny holes, which are called cavities.
    c) If left untreated, cavities can become bigger and cause pain or infection.

    Taking care of your teeth is essential to prevent tooth decay. Some important tips for good oral hygiene are:

    1. You should brush your teeth at least twice a day, using a soft-bristled toothbrush and toothpaste.
    2. Flossing is important because it helps remove food particles between the teeth, where toothbrush can't reach.
    3. Try to limit sugary and sticky foods, like candies, cookies, and sodas. These foods can contribute to tooth decay. Instead, eat more fruits, vegetables, and dairy products like milk and cheese, which are good for your teeth.
    4. Regular dental visits help keep your teeth healthy and catch any problems early. The dentist can examine your teeth, clean them, and check for any signs of decay or other oral health issues.

    Frequently Asked Questions

    1. What are temporary teeth?

    Temporary teeth, often known as baby teeth, are the initial set of teeth that children grow. These teeth begin to appear at the age of six months, gradually replacing the gums' initial emptiness with a set of bright whites.

    2. What is the outermost layer of a tooth called, and why is it important?

    The outermost layer of a tooth is called enamel. It is important because it shields the tooth from decay and keeps it strong and healthy.

    3. Can eating certain foods keep our teeth healthy?

    Yes, eating a balanced diet with calcium-rich foods, such as dairy products and leafy greens, helps keep our teeth strong and healthy.

    4. What can happen if tooth decay is not treated?

    If tooth decay is not treated, it can spread deeper into the tooth, affecting the dentin and pulp. This can cause pain, and infections, and may even lead to the tooth needing to be removed.

    5. What are wisdom teeth?

    Wisdom teeth, also known as third molars, normally develop in the late teens or early twenties.

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