Periodontal apparatus

What is the periodontium?

The periodontium, also known as the periodontium, describes the structures that fix the tooth in the jaw. This means that the root of the tooth is not simply stuck in the jaw, but is anchored via the periodontium. The roots of the teeth are located in bone pockets, the so-called alveoli.

The periodontium represents the fixation of the roots in the bone pockets. The part of the upper or lower jaw bone that accommodates the bone fans is called the alveolar process. In addition to anchoring the tooth, the periodontium ensures damping of the forces acting on the teeth, which can occur, for example, when biting firmly.

Anatomy of the periodontium

The parts that form the periodontium as a unit are 1. alveolar process (Processus alveolaris) 2. root cement 3. periodontal membrane (Desmodont) 4. gum (gingiva) The root of the tooth is covered by the root cement (cementum dentis) Towards the tip of the root, the cement is stronger than towards the top of the tooth crown. Different cement compositions can be differentiated according to their location. The periodontal membrane (Desmodont) fills the gap of about 0.1 – 0.3 mm between the root cement and the alveolar bone.

The periodontal membrane consists of a tight, collagenous connective tissue, the so-called Sharpey fibers. The fibers pull back and forth between the cement and the bone, thus ensuring the actual anchoring of the tooth in its alveolus (bone cavity). Furthermore, nerves and blood vessels run through the periodontal membrane, which at the tip of the root enter the tooth and the pulp and supply the tooth.

The gum (gingiva) surrounds the crown of the tooth (the part of the tooth that is visible in the mouth) like a cuff. It is also part of the periodontium. It is indented towards the root of the tooth so that a small furrow is created in the depth. This is called a gum pocket. If the gums and periodontium are healthy, this pocket should not be deeper than 2-3 mm.