Periodontal Ligament Flashcards
What is the PDL?
fibrous connective tissue that connects the cementum to the alveolar bone
What is the function of the PDL?
attaches tooth to jaw
sensory
eruption
transmits biting force to alveolar bone
What does the PDL contain?
cells (mostly fibroblasts)
blood vessels (highly vascularised)
ECM
nerves
fibres (collagen)
What is the ECM made out of?
hyaluronate glycosaminoglycans
proteoglycans
glycoproteins
How does the ECM behave?
a viscous elastic gel
What cells does the PDL have?
fibroblasts
cementoblasts
osteoclasts and cementoclasts
epithelial cells
defence cells
What are the sensory receptors of the PDL?
nociceptors
mechanoreceptors
What does the sympathetic autonomic innervation control?
blood vessel control
What is unique about the periodontal ligament tissue?
it is similar to foetal tissue therefore dental stem cells can be harvested
What are the two main periodontal fibres and what Is their function?
principle periodontal ligament: fibres connecting tooth to bone at or apical to alveolar crest
gingival ligament: fibres mainly above the alveolar crest including free gingival fibres
What are the alveolo-dental ligament fibres?
alveolar crest
horizontal
apical
oblique
inter-radicular (in multi-rooted teeth)
What is the interdental (between teeth) ligament fibre?
transeptal fibre
What are the functions of these oblique periodontal ligament fibres?
resist the biting force
suspend the tooth within the socket
Relative to the tooth and bone, in which direction do the periodontal ligament fibres run?
From the bone into the cementum
What type of tissue is the periodontal ligament?
dense fibrous connective tissue
