Lamina dura

from Wikipedia, the free encyclopedia
1. Tooth 2. Tooth enamel 3. Dentin (dentin) 4. Pulp cavity with pulp 5. Crown pulp 6. Root pulp 7. Root cement 8. Tooth crown 9. Cusps 10. Fissure 11. Tooth neck 12. Tooth root 13. Bifurcation 14. Root tip 15. Foramen apical 16th gingival sulcus 17, attachment apparatus 18 gums 19 oral or vestibular marginal 20 21 22 alveolar ligament with Sharpey's fibers 23. alveolar bone (the fine yellow line is the lamina dura). 24. Vessels and nerves: 25. Pulp 26. Periodontium 27. Mandibular canal .

The lamina dura ( Latin: lamina or lamna , plate, sheet, sheet and dura , durus , hard) is the cortical portion of the alveolar bone that forms the bony wall of the alveoli. In the 0.1-0.4 mm thick, perforated bone radiate as Scharpey'sche fibers designated elastic collagen fibers of the periodontal membrane a.

anatomy

The attachment apparatus ( periodontal ligament ) is the functional anchoring system of the tooth. It consists of the gums ( gingiva ), the dental cement ( cementum ), the periodontal ligament ( periodontal membrane or ligament. Periodontal ) and the tooth socket ( alveolus ).

The tooth cement and the tooth socket are connected by the Scharpey's fibers ( Fibrae cementoalveolares ) of the periodontal membrane . These collagen fibers are formed by fibroblasts of the periodontal membrane and ensure a tight but flexible connection as well as the load-dependent activation of the osteoblasts .

The Scharpey's fibers radiate into the tooth socket through its thin, perforated outer plate, which consists of cancellous bone and is known as the lamina dura.

Radiological diagnostics

Arrows mark an example of a bright (radio-opaque) line, the lamina dura

The lamina dura is very important in radiological diagnostics. On an x-ray , it can be seen as a radiopaque structure surrounding the tooth root . The periodontal gap visible in the x-ray of a healthy tooth is bounded on the one hand by the root surface and on the other hand by the lamina dura.

The tooth supporting apparatus is one of the finest anatomical structures that can be represented by x-rays. The lamina dura is of great importance for the detection of pathological changes in the tooth support system. An intact lamina dura often suggests that the teeth support system is healthy. Conversely, an incomplete or even missing lamina dura indicates a disease associated with damage to the periodontium.

In periapical ( lat . Apex localized lesions, such as in a: Peak ') radicular cyst is to maintain the lamina dura an important X-sign. On the other hand, the inflammation of the tooth holding apparatus ( apical periodontitis ) starting at the tip of the tooth causes resorption of the lamina dura.

Individual evidence

  1. ↑ Fritz Clemens Werner: Word elements of Latin-Greek technical terms in the biological sciences. Suhrkamp Taschenbuch, 64th Frankfurt / Main 1972 (1st edition); 2003 (9th edition). Page 237. ISBN 3-518-36564-9 )
  2. ^ A. Fuhrmann: Dental radiology, Thieme publishing house. 1st edition (2013) ISBN 978-3-13-165341-3
  3. ↑ J. Kirsch, CA May, D. Lorke, A. Winkelmann: Pocket textbook anatomy, Thieme publishing house. 1st edition (2010) ISBN 978-3-13-144991-7
  4. ^ A. Fuhrmann: Dental radiology, Thieme publishing house. 1st edition (2013) ISBN 978-3-13-165341-3
  5. ↑ Jürgen Düker: X-ray diagnostics with the panoramic layer image:. Additional work: Jürgen Düker . Georg Thieme Verlag, January 12, 2000, ISBN 978-3-13-155572-4 , p. 434.
  6. ↑ FA Pasler, H. Visser: Pocket Atlas of Dental Radiology, Thieme publishing house. 1st edition (2003) ISBN 978-3-13-128991-9