Teeth are a highly complex part of the human body. Teeth are mainly made up of proteins such as collagen and minerals such as calcium. Teeth not only help you chew food, but they also shape your face and play an essential role in helping you speak clearly.
Depending on their shapes, the teeth in our dental cavity and anatomy perform different functions such as cutting, shearing, tearing, crushing and grinding.
What Do You Need to Know About the Anatomy and Types of Teeth
Tooth development begins long before your first teeth are visible. Teeth usually grow in pairs symmetrically. The upper and lower molars on the left side come out simultaneously with the upper and lower molars on the right. As a person ages, the number and types of teeth that person has also changes.
Teeth Growth from Babies to Adulthood
Typically, people have two sets of teeth in their lifetime – the primary (or baby teeth) and permanent (adult teeth). A baby’s first teeth appear at more than six months of pregnancy. However, tooth development begins as early as the second trimester. Between the ages of 2 – 3 years, children would have grown 20 primary teeth. Those ten teeth in the upper and lower jaw are:
- four incisors
- two canines
- four molars
Children tend to lose their primary teeth between the ages of 6 and 12 years. By 12 years of age, most children should have their primary teeth replaced by a complete set of permanent teeth, excluding wisdom teeth. People typically have all of their permanent teeth in place by the time they are 21 years of age.
The Types Of Teeth and Their Functions
There are four different types of teeth in our oral cavity: incisors, canines, premolars and molars. Most adults have 32 permanent teeth made of:
- 8 incisors
- 4 canines
- 8 premolars (front molars)
- 12 molars (4 of them wisdom teeth)
Teeth have different shapes as each tooth has a particular role to perform during chewing and digestion. They are also positioned differently for their respective role in the mouth. Continue reading to learn more about the different types of teeth, shapes and functions.
Incisors
The incisors are the most visible teeth in the human mouth. They are four front teeth in the upper and lower jaws, shaped like small carving tools with sharp edges. Their primary function is to bite and cut food into small, chewable pieces. In addition, incisors also help pronounce words and support the lip.
Incisors are usually the first teeth that will erupt when a baby is around 6 months old. They will eventually fall out and be replaced by a permanent set of incisors between 6 and 8 years old.
Canines
Canine teeth are the easiest to recognize because of their sharp, elongated and pointy look. These teeth are positioned directly next to the incisors. Their primary function is to rip and tear food apart, such as meat, hard fruits and vegetables.
In infants, the first canine teeth erupt around the ages of 16-20 months. Generally, the upper canine teeth grow first, followed by the lower canines. They are then replaced by permanent canines between the ages of 9 and 12, which emerge oppositely. The permanent lower canines usually appear before the permanent upper canines.
Premolars
Premolars sit next to your canines. There are eight premolars in total, four on top and four on the bottom row of teeth. Premolars are larger than canines and incisors. The surface is flat, and it helps crush or grind food into smaller pieces, making it easier to swallow. In addition, premolars also help keep the shape of the face. One’s appearance can change due to the absence of premolars.
Adult premolars replace the baby molar teeth. Babies and young children don’t have premolars because these teeth only emerge around age 10.
Molars
Molars are the largest and strongest teeth, located in the farthest back part of the mouth. You have six on top and six on the bottom, totalling 12 molars. The large surface of molars helps break food down, essential for eating normally. When the incisors have chewed the food into smaller pieces, the tongue will help push the food towards the back of the mouth. Then, the molars continue the chewing process and crush and grind the food.
The molars include four wisdom teeth, also called third molars. They are the last set of teeth to come in, usually between 17 and 25 years old. When there’s not enough space in the mouth for the wisdom teeth to grow, you will likely remove them through a surgical process.
Layers of Types Of Teeth Anatomy
Now that we have learned about the types of teeth, let’s look at their anatomy and structure.
Enamel
Enamel is the outermost layer of the tooth and the strongest, and it protects the tooth from bacteria and various stimulants, such as cold and heat. The enamel coating is white ivory and slightly transparent, made of multiple minerals, including calcium phosphate.
Dentin
Dentin is the layer beneath the more densely coloured enamel and is the more sensitive part of the tooth. The dentin layer has micro holes that are connected to nerve endings. If the enamel layer of the teeth is damaged, painful stimuli such as hot food and cold drinks will easily cause pain and sensitivity.
Pulp
The pulp is the tooth’s softer innermost layer. Nerves and blood vessels run through the teeth’ pulp and reside within the tooth’s center. This layer is connected to the root canal. If bacteria enters and this gets infected, it may become painful, and you will need either a root canal or tooth extraction.
Cementum
Cementum is also called cement. This bone-like material is a calcified or mineralized connective tissue layer that firmly covers the tooth’s root. The layer also binds the teeth’ roots to the gums and jawbone. The cementum allows the periodontal ligament, jaw bone and gums to attach firmly to a tooth.
Periodontal Ligament
The periodontal ligament (also known as PDL) comprises connective tissue, collagen fibres, nerves and blood vessels. Together with the cementum, this layer keeps the tooth in its socket. The PDL tissue is naturally complex; it allows the tooth to function correctly during chewing and withstand grinding or clenching.
Conclusion
Teeth are essential for grinding, chewing and biting food properly. Taking good care of your teeth and mouth hygiene helps maintain oral health and prevent dental disease. The most straightforward step is brushing teeth at least twice a day, after breakfast and before sleeping. Flossing and avoiding excess sugar in food and drinks also helps.
A regular dental checkup is also advised for maintaining oral health. Schedule an appointment at Eastman Dental for professional cleaning and a checkup to ensure your teeth remain healthy and treat any problems early.