Histology Of Periodontal Ligament Flashcards
What is the PDL
The periodontal ligament is a connective tissue that surrounds the root and connects it with the bone, it is a continuation of the gingiva, has a rich blood supply.
What are the functions of PDL
. Nutritive (rich blood supply - nutrients)
. Sensory (nerve fibres, picks up sensations)
. Physical
When does the PDL form
It forms shortly after the root development begins
Describe the development of the PDL
Root needs to be formed before PDL is layered down, gingival fibres comes first, collagen layers down then get organised
What are the structural elements of the PDL
What are the blood and nerve supply to the PDL
Blood supply - apical vessels, penetrates through alveolar bone, vessels from the gingiva
Nerve supply - sensory and autonomic
What reduces blood supply in PDL
Smoking
What are the fibres groups in PDL
. Alveolar crest
. Horizontal
. Oblique
. Apical
. Interradicular
(Explanation of each of them on good notes)
In the structure of PDL it has ground substance what is it and its functions
It’s an extracellular substance and it contains collagen fibres, water, tissue fluid (high pressure)
It’s function is it gets rid of toxins, keeps everything at a consistency
What are the changes in age of PDL
. Decrease in cells
. Decrease in vascularity
. Narrowing of PDL
Why are fibres in PDL unorganised
So it can be everywhere, no matter what direction you put pressure on the tooth it can cope with it
Dental implants have which of the following fibres?
A. Alveologingival fibers and circular
What are two scaffolding fibers of the PDL and their function
Explain the formative and resorptive function of the periodontal ligament
The width of periodontal ligament must be maintained
Formative – contains cell builders, cementoblasts and osteoblasts
Resorption of hard tissues of periodontium – repair bone & cementum, degrade old cells, maintain width of PDL space
The periodontal ligament is rich in various types of cells. Provide two examples of resorptive cells in the periodontal ligament
Osteoclasts
Fibroblasts
Cementoclasts
