3rd South Dental

The Anatomy of a Tooth

An illustration highlights various layers of a tooth.

The Anatomy of a Tooth

An average adult human has a mouth full of 32 pearly whites. Except for wisdom teeth, adults have their full set of permanent teeth by the age of 13. Unlike our milk teeth, these 32 are meant to last a lifetime, and are made of the materials that with a good diet and daily hygiene can last you forever.

The Different Types of Teeth

Of our 32 teeth, we have 8 incisors, 4 canines, 8 premolars, 8 molars and 4 wisdom teeth. Incisors are the middlemost four teeth of our top and bottom jaws. These teeth support our lips, bite into food and help you pronounce words. Canines are the pointed edged teeth that sit on the outside of our incisors and are used to cut our food. Premolars sit behind our canines and are best used to chew food. Our molars are some of the last teeth at the back of our mouths and do the job of grinding our food down even further. Wisdom teeth, which only erupt after the age of 18 and are normally removed, take up the space at the very back of our mouths and do the same job as molars.

Although we have various different kinds of teeth that do different jobs in our mouth, each tooth is made out of the same layers.

The Layers of a Tooth

Believe it or not, but your teeth are the hardest natural substance in your body. Each tooth is made up of five layers that connect it to the rest of the mouth.

Layer One – Enamel

Much like enamel paint, your tooth enamel creates a hard, glossy coat over the exterior of the tooth. Unlike the paint, tooth enamel is made up of calcium phosphate, which is a rock-hard mineral. It is the front line of defense against bacteria and decay in the mouth. Without our enamel, bacteria is able to infection the soft tissue interior of the tooth, which can result in an extraction or a root canal.

Layer Two – Dentin

Beneath the white, glossy enamels, is a thicker layer called Dentin, which is a hard tissue that contains microscopic tubes. Dentin is more sensitive than enamel as its tubules communicate with the nerve endings in your tooth. When dentin is exposed, your teeth become more sensitive to the changes in hot and cold temperatures in the food you eat and what you drink.

Layer Three – Pulp

Now we start to see the softer side of the tooth. The third layer of the tooth consists of pulp, a soft, living tissue that is filled with blood vessels and nerve endings. The pulp is what keeps the tooth alive, without it the tooth would not respond to temperature or other stimuli. Pulp also helps form dentin and provides nutrients and moisture to areas around the tooth.

Layer Four – Cementum

This layer binds the root of the tooth to the gums and jawbone with connective tissue. You could say that cementum is the reason why we have rows of teeth at all. Such an important job needs to be undertaken by a strong material, and this is why cementum tissue structure is similar to that of bone.

Layer Five – Periodontal Ligament

The fifth and final layer of a tooth is the Periodontal Ligament. This tissue assists in holding the tooth to the jawbone.