Why are my teeth different shapes?

Teeth can be defined as the hard, resistant structures occurring on the jaws that play an important role in catching and masticating food, for defence and several other important functions.  Human teeth are of various different shapes because each tooth type has a different function while chewing food. Different shapes of teeth have different functions and help humans chew their food down and avoid choking on it.

Human beings have four types of teeth which are as follows:

•  Incisors – The four teeth present front and centre in both the upper and lower jaw are known as incisors.   Their function is to cut food into small pieces as you start the chewing process. They are thin and flat in shape. The two teeth on either side of the midline are known as central incisors whereas those on either side of the central incisors are known as lateral incisors.
• Canines – They are present behind and adjacent to the incisors. They are also called ” Vampire Teeth”. There is a total of four canines in the oral cavity, two in the upper jaw and two in the lower jaw. They are the sharpest teeth present in the oral cavity. They help by gripping and tearing food while chewing process.
• Pre-Molars(Bi-cuspids) – They are located behind and adjacent to the canines. Their function is to crush and grind food, making them small enough to be swallowed.  There are 8 pre-molars in total, two in each of the four quadrants of the mouth. The one closest to the midline is called the first pre-molar and the one next to it is called the second pore-molar. These teeth can have 3-4 cusps.
• Molars – These are large, flat teeth located in the innermost part of the oral cavity. They have about 4-5 cusps and are primarily used to grind food. There a total of 12 molars, there in each quadrant of the mouth. The molars are named as first, second and third according to their proximity to the midline. The third molar commonly referred to as wisdom teeth, do not completely erupt until later in life. The time varies and can appear anytime between late teens to early twenties or even later.

The teeth are the toughest substance in the human body. They have the function of chewing food and helping in the speech.

Different parts of the teeth:

• Enamel- Enamel is the outermost covering of the tooth. It is the hardest substance present in our body. Its main function is to protect dentine from wear and tear. It is majorly made up of calcium phosphate.
• Dentine- Dentine is the main supportive structure of a tooth present just underneath the enamel. It is largely made up of approximately 30,000 – 40,000 dentinal tubules per square millimetre. These tubules transmit pain to the pulp if they are exposed to damage. The main function of dentine is to prevent any harm to the pulp.
• Pulp- It is the innermost part of the tooth consisting of vascular, nervous and lymphatic supply. The main function of the pulp is to create dentine and to provide nutrition to the tooth. Pulp is made up of living connective tissues known as odontoblast.
• Cementum- Cementum covers the roots of a tooth. Its main work is to secure a tooth by binding its roots to gums and jawbone.

Fun Facts:

1. Only 1/3 part of your tooth is visible outside. The other 2/3 parts are inside the gums
2. The tooth is the only body part that can not heal itself. Hence, you should take proper care of your teeth.
3. The first set of teeth also called baby teeth are just 20 teeth in total, whereas the second set of teeth that is adult teeth include 32 total teeth.

Additional Questions:

1. Define teeth and their basic functions.
2. Describe briefly the different types of teeth present in humans.
3. Which are the sharpest teeth in our mouth?

True or False:

1. Enamel is the hardest substance present in the human body.
2. The pulp part of teeth is connected to the nervous system.
3. Premolars are situated in the front most part of the mouth.
4. Different shapes of teeth are given so that breathing can be made easy.
5. Wisdom teeth are present in the mouth from the birth itself.

Objective Quiz:

1. There ________ types of teeth present in human being.

• Two.
• Three.
• Four.
• Six.

2. Incisor helps by ______________.

• Cutting food into small pieces.
• Grinding food.
• By crushing food.
• All of the above.

3. Molar are present in __________ number in adult human being.

• Five.
• Nine.
• Eight – Twelve
• Eight.

4. Dentine is present ____________.

• Just under the enamel.
• Just under the pulp.
• Just under the cementum.
• It is the outermost covering of the tooth.

5.___________ are also called as Vampire Teeth.

• Molars.
• Canines.
• Pre-molars.
• Incisors.