Periodontal Ligament Flashcards
1
Q
What is periodontal ligament?
A
A connective tissue
2
Q
What does periodontal ligament contain?
A
- Cells
- ECM
- Fibres
- Nerves
- Blood vessels
3
Q
What does periodontal ligament matrix contain?
A
- Hyaluronate glycosaminoglycans
- Proteoglycans
- Glycoproteins (proteins with carbohydrates attached to it)
4
Q
What is the property of periodontal ligament matrix?
A
- Behaves as a viscous elastic gel
- Absorbs water and becomes jelly like structure to become viscous elastic gel, acts as a suspension for extreme forces applied to teeth
- As you bite, forces need to be transformed to bone without damaging bone
- Dentine and enamel is harder than bone
5
Q
What cells are present in periodontal ligament?
A
- Fibroblasts (produces collagen and other fibres)
- Cementoblasts (formation of cementum)
- Osteoclasts and Cementoclasts
- Epithelial cells
- Cell rests (or debris) of Malassez
- Defence cells
6
Q
What sensory nerves are present in PDL?
A
- Mechanoreceptors (will act upon forces)
- Nociceptors (There to recognise any extreme and dangerous force, which causes reflex to protect from damaging teeth)
7
Q
What is the autonomic (sympathetic) control of the nerves in the PDL?
A
- Blood vessel control
- Vasoconstriction
8
Q
What is true periodontal ligament?
A
- Fibres connecting tooth to bone at or apical to alveolar crest
9
Q
What is gingival ligament?
A
- Fibres mainly above the alveolar crest, including ‘free gingival’ fibres
- Gives support to gingiva surrounding the tooth - might be connecting tooth or bone to gingiva or just providing support
10
Q
What does PDL transmit to alveolar bone?
A
Biting forces
11
Q
Where does alveolo-dental ligament connect?
A
- Alveolar crest
- Horizontal
- Oblique
- Apical
- Inter-radicular (multi-rooted teeth)
12
Q
Where does interdental ligament connect?
A
- Trans-septal fibres (fibres connecting tooth to other tooth - need to be in between teeth)
