What Is Cementum?

Cementum is a hard, calcified tissue that covers the root of a tooth and plays a vital role in supporting dental structure. Its main function is to help anchor the periodontal ligament, the connective tissue that secures the tooth to the surrounding bone.

Cementum forms gradually over a person’s lifetime and is produced by specialized cells known as cementoblasts. Though not fully understood, cementoblasts are essential to the slow and steady growth of cementum. This tissue is yellow in color, softer than dentin, and chemically similar to bone. However, unlike bone, cementum is avascular, meaning it doesn’t have its own blood supply.

Cementum serves as the attachment surface between:

• The outer root of the tooth

• The periodontal ligament on the outside

• The dentin on the inside

Together with the gingiva (gums), alveolar bone, and periodontal ligament, cementum helps keep your teeth firmly in place.

Types of Cementum

There are three main types of cementum:

• Acellular Cementum:

  • Covers the upper portion of the tooth root (about one-third to one-half) and contains few or no cells.

• Cellular Cementum:

  • Found closer to the root apex (tip), it is more permeable and contains living cells.

• Afibrillar Cementum:

  • Sometimes extends slightly onto the enamel surface near the gum line. It lacks the fiber structure typical of other types.

Cementum and Gum Disease

In cases of periodontal disease, any of these cementum types may become infected or compromised. Scaling and root planing, also known as deep cleaning, can remove diseased cementum, dental tartar, and infected dentin to help restore gum health and prevent further progression.

If it’s been a while since your last dental visit, or if you’re experiencing signs of gum disease such as bleeding or swollen gums, schedule an appointment today. Early care can help preserve the structures, like cementum, that keep your smile strong and healthy.