Imagine a nice, hard, juicy red apple. This apple is given to you when you have reached the threshold of controlling your hunger. You try to take a big bite, alas, your gums just slide through the skin of the apple. What seems to be missing in this picture? Yes, you are right, teeth. Teeth help us take that very important bite of an apple and further helps us chew the apple piece into a more digestible matter. Each person has different set of teeth that not only help chewing and biting things, but also help you tear off a thin cloth, grip things in your mouth and yes, they are a very good self-defense tools at times. You can just bite off an attacker and run for your life. Teeth also help give our face a proper structure and add to the cosmetic beauty of our face. Just imagine a toothless smile of a 80-year-old grandma, you will know the cosmetic importance of your teeth. There are many more functions of the teeth. They help control the airflow through the mouth, thus making our speech much clearer and audible to hear. We can smile and control the facial muscles around the jaw. There are about 32 teeth in the human jaw. There are 16 teeth in the upper jaw and 16 teeth in the lower jaw. Humans grow their teeth in 2 sets. The first set is called the 'milk teeth' or 'baby teeth'. These teeth make an appearance around 6 months of age and the complete set will be in place by the age of 6 years. Then, these 'milk teeth' will soon begin to loosen up and will fall out one by one from the root. Once the baby tooth falls off, a new tooth will take its place. This is the permanent tooth, if lost will never be replaced. Human teeth are called heterodonts. Different types of Human Teeth The teeth present on the right side of the jaw are similar to the teeth on the left side. Thus, they are a pair of similar shaped and sized teeth. Each pair of teeth has a particular function. The front teeth help in taking a bite. The teeth at the back of the mouth are designed to help chew food. Each of these different types are discussed below. Incisors The flat, straight, sharp-edged teeth in the front are called incisors. These teeth are also called cutting teeth. There are 4 incisors in the upper jaw and 4 in the lower jaw. Thus, there are a total of 8 incisors in humans. These help us to cut and bite food into smaller pieces, such that it can be easily chewed by the other teeth. Incisors are the first to appear in children. They are therefore also called baby teeth. Canines The canines are also known as eye teeth or cuspids. They are long pointed teeth that help in tearing down food. There are two canine teeth in the upper jaw and two in the lower jaw. The canines are said to be the longest teeth. They have a single root and are the only teeth with a single cusp, thus called cuspids. This means they have a round projection on the chewing surface of the tooth. Pre-Molars The teeth present behind the canine teeth are called pre-molar teeth. Pre-molars have about 1 to 2 roots. They are also called bicuspids as they have flat upper surface with at least 2 cusps. The function of pre-molars is to chew and crush food. There are a total of 8 pre-molars in the adult human mouth. Molars The last teeth in the back of the mouth are called molars. There are 3 molars in each quadrant, thus bringing the total to 12 molars. These teeth have the largest surface and help in chewing and grinding of food. Once the food is ground by the molars, it is swallowed. There are 2 to 4 roots that anchor the molars into the jawbone. Third molars usually appear late in life and cause a lot of pain and discomfort. These teeth are called wisdom teeth. In most cases, one has to remove the wisdom teeth due to lack of space or an infection. Human teeth are made up of enamel, dentin, pulp and cementum. It is important to maintain good dental health to avoid tooth infection, cavities, gingivitis, bad breath and even losing a tooth or two. A visit to the dentist may be one of the most scariest thing. But, it will surely help maintain a long-lasting smile.