Teeth form one of the hardest and toughest parts of our body. They are basically useful for chewing and cutting down the food into smaller particles and also aid in speaking.
A tooth is formed from three tissues – enamel, dentin, and pulp, from outwards to inwards. Collagen and some other proteins constitute a tooth.
Contents
What Are the Types of Teeth?
Primary dentition in humans consists of 20 teeth in total, while, secondary dentition consists of 32 teeth. This is known as the diphyodont condition.
Humans also have a heterodont dentition, which means, there are different types of teeth present in the human jaw.
– During the deciduous or primary dentition period, teeth in each jaw are:
- Incisors- 4
- Canines- 2
- Molars- 4
– During permanent or secondary dentition, teeth in each jaw are:
- Incisors- 4
- Canines- 2
- Premolars- 4
- Molars- 6
Tooth eruption starts when the baby is about six months old and continues up to the age of 3-6. From the age of 6 to 12, the child starts losing its deciduous teeth to be replaced by permanent teeth.
An exception to this is, premolars have no predecessors. Permanent dentition keeps forming until the last wisdom tooth appears, mostly by the age of 17-21.
What Are Incisors?
Incisors are usually the first set of teeth to appear when the baby is about 6 months old. Permanent incisors appear from 6 to 8 years of age.
There are eight incisors in total, four in each jaw. These are further divided into central and lateral incisors. They are located in front and are straight and chisel.
Incisors are used for biting into the food when it is first placed in the mouth.
What Are Canines?
Canines form the sharpest set of teeth in the mouth They are located next to lateral incisors and are 4 in number, in both, primary and secondary dentition. They appear when the baby is 16-20 months old.
Mandibular (lower) permanent canines start to erupt about the age of 9 and maxillary (upper) permanent canines appear about the of 12.
Due to their pointy edges, they are used for tearing the food apart, to break it into smaller particles. They also serve in the formation corners of the mouth.
What Are Premolars?
Premolars are located next to canines, but, only in permanent dentition. As said above, they do not have any predecessors. They appear between 9 to 13 years of age.
In the buccal cavity, there is a total of eight premolars, 4 in each jaw and 2 in each quadrant.
Maxillary first premolar holds an exception in that it has two roots, while, all the other premolars have a single root.
Premolars have flat surfaces and consist of ridges. Their function includes crushing and grinding of food into finer particles to allow easier swallowing.
What Are Molars?
Molars are the last teeth in both primary and secondary dentition to be present in a jaw. They are the most posterior teeth.
There is a total of 12 molars present in the oral cavity and they are designated as first, second, and third molar depending upon location from the midline.
The first two molars in each quadrant grow between 6 to 12 years of age and the third molars grow between the age of 17 to 25, known as wisdom teeth.
Since jaws are of different sizes, some cannot accommodate the last formed wisdom tooth. This can lead to cases where the wisdom tooth is stuck under the gums (impacted), due to which, it needs to be removed by the doctor.
They have broader and flatter surfaces with a larger area. This makes them suitable for grinding the food particles into a smaller size when the tongue pushes back the food for proper swallowing.
Conclusion
Teeth form an essential part of our body. Without them chewing and swallowing of the food particles would not be possible. There are different types of teeth present in humans and they appear at different times of age.
Since teeth don’t remain intact throughout life, it is important to take good care of them and regular checkups to the dentist are also important.
