Periodontium Flashcards
What is the role of the PDL?
Attach tooth to alveolar bone.
Transmits biting forces to alveolar bone
Defensive barrier- protecting tissues against threats from the oral environment.
Describe the components of the PDL?
Cells- fibroblasts, cementoblasts, osteoclasts, cementoclasts, defence cells, epithelial cells
Extracellular matrix- proteoglycans, glycoproteins
Nerves- mechanoceptors, nociceptors, sympathetic control.
Fibres
Blood vessels.
What are the fibres that make up the alveolo-dental ligament?
Alveolar crest
Horizontal
Oblique
Apical
Inter-radicular (multi-rooted teeth)
What are the interdental ligament fibres?
Trans-septal fibres.
If someone has a denture, how does this impact how the occlusal load is distributed?
Forces are transferred to the gingiva and not the bone.
Gingiva is not as strong as bone, can’t generate the same amount of force.
Alveolar bone resorbs because there is no longer any force being applied to the bone.
There are also no mechanoceptors because there is no PDL, won’t be Abel to detect the biting forces.
What are the canals called within alveolar bone, what allow the passage of blood vessels and nerves?
VolkMann’s canals.
Describe the composition of alveolar bone.
Cortical plate forms the inner lining of tooth socket.
Penetrated by Volkmann’s canals.
Inner cancellous bone has bone marrow.
What is the difference between the junctional epithelium and the sulcular epithelium?
Junctional epithelium lies immediately apical to the sulcular epithelium.
Junctional- most apical part of the gingival sulcus, this is what you are probing when you look for probing depth.
Sulcular epithelium- lines the gingival sulcus, goes from the junctional epithelium to the gingival margin.
What cells attach the junctional epithelium to the enamel?
Desmosomes attach the junctional epithelium cells together and the hemidesmosomes attach the epithelial cells to the enamel.
