An adult human has 32 teeth at the age of 21. But all teeth are not of same type. Some teeth are different from other groups due to their shape. Change in the shape of the crown of various teeth can be easily seen in the reflection of your teeth in a mirror. The roots of the teeth also vary, but it is not visible to the human eye. Teeth are of various types in order to assist in various tasks of eating like cutting, shredding and grinding of the food materials.
These are also termed as cutting teeth and an adult human being will have 8 incisors. There are four each in the very front part of your upper and lower jaw line. Their crown is a flat surface and each incisor has one cone shaped root. Incisors are instrumental in biting and cutting food items.
There are 4 canines, one on each side of the incisors in the upper and lower jaw line. These are sharp pointed and strong teeth useful for tearing and shredding. The canines have a conical crown and are longer than other teeth. They have a single root which is longer than other roots.
Also known as bicuspid teeth, premolar are used for chewing purpose. There are 8 premolars, two on each side of the canines in the upper and lower jaw line. The crown of this tooth type is flat but has two cusps or pyramidal eminences. These teeth have 1 or 2 root.
There are totally 12 molars, three on each side of the premolars in the upper and lower jaw line. Molar teeth have comparatively larger upper surface and 2 to 4 roots. This type of tooth is the largest of all other types of tooth. These teeth are useful for fine chewing and grinding purpose of the food items. Sometimes, the third molars are referred to as wisdom teeth. This wisdom tooth will erupt in the age between 17 and 21.