Periodontium

Periodontium components <br><br><br><br><br><br>

The parodontium includes all parts contributing to dental anchoring. The structure of the parodontium also dampens the forces working on the teeth, which can have a bite force of up to 80 kg. The dental roots are located in the alveolae. The proportion of the upper and lower jaw bone containing the alveoli is called the alveolar process. The tissue parts attaching the teeth in the alveoli and form the parodontium are:

  • The alveolar process (processus alveolaris),
  • Root cementum,
  • Periodontium (desmodont),
  • Gingiva

The root cementum covers the dental root from the neck to the root tip. The fibres of the periodontium growing towards the alveolar bone are connated with the root cementum. It primarily serves to anchor the tooth in the alveolar.

onnective tissue fibres are the main components of the periodontium. They connect the alveolar bone in the alveoli with the tooth's root cementum. The fibres radiate into the compact bone layer of the alveolar wall. The individual teeth are thus not connated with the alveolar bone but rather suspended in the alveoli through connective tissue fibres. Therefore the pressure of chewing and biting is converted into tensile loading.

Apart from connective tissue fibres, the periodontium also contains a dense network of blood vessels, which not only supply the cells of the root cementum but also dampen the chewing pressure. The periodontium also contains nerve fibres which convey the teeth's sense of pressure and touch.
The alveoli for the teeth are located in the jaw's alveolar process. In a healthy periodontium, the bone starts approx. 1 to 2 mm below the border between the root cementum and the enamel.

Gingival and mucosal structure

The gums (Gingiva) not only cover the area of the tooth neck and the upper part of the alveolar process, but they also form one interdental papilla as interdental gingiva in the area between the teeth. The free or marginal gingiva proceeds in wave form parallel to the tooth necks like a narrow seam of even width. The width is approx 1.5 to 2.5 mm. Connective tissue fibres within the marginal gingiva also run to the dental cementum and to the alveolar bone. The marginal gingiva adheres to the tooth neck area with the help of a special junctional epithelium.

Attachment of the gingiva at the alveolar bone and root cementum

A 1 to 2 mm deep gingival furrow, known as sulcus gingivae, is located between the tooth surface and the marginal gingiva. It is rinsed with liquids from the tissue and saliva. If a parodontal probe measures a sulcus depth of 3 mm and more, a parodontal pocket applies, which requires treatment to retain the tooth. The junctional epithelium forms a circle around the tooth neck. It forms the base of the gingival furrow or the parodontal pocket and adheres to the tooth. In this way it seals the bone from the oral cavity's external influences.

In contrast to the marginal gingiva, the 1 to 9 mm wide attached gingiva (or Gingiva propria) on the alveolar bone is non-relocatable. It is pale pink and has a dull, stippled surface. These stipplings are created by the traction of the connective tissue fibre bundles on the underside, which ensure the attachment to the periosteum of the alveolar process and at the root cementum. The attachment is strong enough to resist the force action during chewing and biting. The attached gingiva merges into the removable mucosa of the alveolar process at the mucogingival junction.