The tooth from crown to root

Whether you look at a sharp incisor, a pointed canine, or a robust molar, the basic structure is always the same. A tooth consists of three main parts: the crown, the neck, and the root.

The crown is the part we see above the gum line. It is covered by enamel – the hardest substance in the human body, which must withstand immense pressure during chewing. Although enamel is extremely durable, it’s not indestructible. Acids in the mouth can gradually erode it, and once damaged, it cannot regenerate on its own.

Beneath the enamel lies dentin, which makes up the majority of the tooth. It’s less hard than enamel and contains tiny channels that lead to the dental pulp. This is why we can feel pain or sensitivity when the dentin is exposed – for example, when consuming something cold. The neck of the tooth is the area where the crown meets the gum. You may have heard of exposed necks – this refers to a condition where the gum recedes and reveals the more sensitive part of the tooth.

Then there’s the root, which anchors the tooth firmly in the jaw. Incisors and canines typically have one root, while molars may have several. The root is covered by a special tissue called cementum and is embedded in the tooth socket, where it is held in place by fine periodontal fibers.

The inner structure of a tooth

If we were to cut a tooth in half, we would see the dental pulp in the center. This is where the nerves and blood vessels are located, providing nourishment to the tooth and transmitting sensations – such as when we eat or drink something hot or cold. The pulp extends from the crown all the way to the tip of the root, and connects the tooth to the body through a small opening at the end of the root canal.

The entire tooth is also firmly connected to the jawbone by the periodontium – the tooth’s supporting apparatus. This includes not only the socket itself, but also the fibers that act like flexible anchors, absorbing shocks when biting. Without a healthy periodontium, teeth wouldn’t be stable – as is the case with periodontitis, where the fibers and surrounding bone are lost, and teeth can start to loosen.

Understanding the structure of a tooth helps us to better understand what harms it and how to care for it properly. Oral care isn’t just about cleaning the enamel, but also about protecting the gums and preventing problems with the dentin and pulp. When we view teeth as a whole system, we can protect them so they last a lifetime – not just until the first sign of pain.