Tooth Anatomy

Do you ever wonder

Anatomy

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Do you ever wonder what your tooth looks like inside? Here is a description of your teeth’s anatomy.

Crown, Root and Neck:

The tooth has two anatomical parts, the crown and the root.

The crown of a tooth is the top part that is exposed and visible above the gum (gingiva). It is covered with enamel, which protects the underlying dentin.

The root of a tooth descends below the gum line, into the upper or lower jawbones, anchoring the tooth in the mouth. Different types of teeth have a different number of roots and root formations. Typically incisors, canines and premolars will have one root whereas molars will have two or three.

The neck is the dividing region of tooth at the gum line, where the crown meets the root.

Enamel:

The crown of each tooth is covered with enamel, which protects the underlying dentine. Enamel is the hardest substance in the human body, even harder than bone. This is because it is the most mineralised substance in the body, made up of crystalline calcium phosphate (Hydroxylapatite). It is as hard as crystal.

Enamel is the only tissue that has no living cells. Because it is not alive, it can’t repair itself from decay or damage.

Gingiva (Gum):

The gingiva is the pink soft tissue that we call our gums. It protects the jaw (alveolar) bone and roots of the teeth, and covers the neck of each tooth.

Dentin:

Dentin forms the major component of each tooth, and extends almost the entire length of the tooth. It is a living tissue, softer than enamel with a structure similar to bone. In contrast to the brittle nature of enamel, dentine is elastic and compressible. It is sensitive, and is protected by enamel on the crown portion and cementum on the roots. It is nourished by the pulp.

Pulp Chamber:

The pulp chamber is the innermost portion of the tooth, lying beneath the dentin and extending from the crown to the tip of the root. The pulp chamber holds the pulp, which is made up of soft tissue. It contains blood vessels to supply blood and nutrients to the tooth to keep it alive, and nerves to enable the tooth to sense temperature. It also contains small lymph vessels carrying white blood cells to the tooth to help fight bacteria.

Cementum:

The cementum is a layer of hard tissue that covers the root of the tooth. It is roughly as hard as bone but considerably softer than enamel. The connective tissues attach to the periodontal ligament, and through this bind the roots of the tooth to the gums and jaw (alveolar) bone.

Root Canal/ Pulp Canal:

The root canal (also called the pulp canal) is the open space inside the root where the pulp extends from the pulp chamber. Blood vessels and nerves from surrounding outside tissue enter the pulp through the root canal.

Periodontal Ligament:

The periodontal ligament is comprised of bundles of connective tissue fibres. One end of each bundle is attached to the cementum covering the root of the tooth. The fibres on the other end anchor the tooth root to the jaw (alveolar) bone and act as shock absorbers, allowing the tooth to withstand the forces of biting and chewing.

Accessory Canal:

Accessory canals are smaller channels that branch off from the main root canal through the dentin to the periodontal ligament. They are usually found near the root end of the tooth (apex). They supply blood vessels and nerves to the pulp.

Apical Foramen:

The apical foramen is the tiny opening at the tip of each root. This is what blood vessels and nerves from surrounding outside tissue pass through to enter the tooth.

Alveolar bone:

The alveolar bone is the jaw bone that surrounds and supports the root of the tooth. It contains the tooth sockets within which the tooth roots are embedded.

 

We at Bell Dental, PA have lots of fun facts about your teeth and oral health. Be sure to ask questions when you come to your appointments if you would like more information.