pulp Flashcards
four distinct zone of pulp
- odontoblastic zone (at the pulp periphery)
- cell free zone (prominent in coronal pulp)
- cell rich zone ( coronal pulp adjacent to cell free zone)
- . pulp core (major vessels and nerves of pulp)
principal cells of pulp
odontoblast, fibroblast, undifferentiated ectomesenchymal, macrophages, and some immunocompetent cells
odontoblast correspond to?
dentinal tubules and depends the the tooth and the location of the tooth
odontoblast in crown and root
in crown they are large columnar and 50 micrometer, midportion of pulp they are cuboidal and apical root they are flattened
tubular fluid contents are
proteoglycans, fibronectin, tenascin and serum proteins which are albumin, HS glycoprotein and transferrin
cells occurring in greatest number in pulp are
fribroblast
fibroblast are found in
coronal pulp at the cell rich zone
function of fibroblast
form and maintain the pulp matrix which consist of collagen and ground substance
in young pulp fibroblast are
actively secreting pulp matrix, plump cytoplasm with all the organelles and
with age what happens to fibrblast
the need for synthesis diminish, they become spindle shaped with dense nuclei,
function of undifferentiated mesenchyme
they secrete the connective tissue of the pulp, depending on the stimulus they can also secrete odontoblast and fibroblast
where undifferentiated mesenchyme cells found
cell rich zone and pulp core
what happens in older pulps,
number of undifferentiated mesenchymal cells diminish including other pulp core cells, and this reduces the regenerative property of pulp along with other age factors.
inflammatory cells of pulp
they have macrophages, t lymphocytes some b lymphocytes and some leukocytes
they also have bone marrow derived antigen presenting dendritic cells
collagen fibers present in pulp and mostly found where and how it is chkowof clinical impact
collagen type I AND III
mostly found in the apical region
when pulpectomy is done in endodontic treatment, the barbed broach should be engaged in the apex rather than the coronal portion where the pulp is gelatinous and liable to tear
ground substances contans
glycosaminoglycans, glycoproteins and water
alternation in composition of ground substance causes
interfere with function, producing metabolic changes, reduced cellular function and irregularities in mineral deposition
sunodontoblastic plexus of raschkow
nerves in pulp chamber follow the course of afferent arteries, then branch off periphery as they extend oclusally in the pulp core, these nerves make a plexus of nerves in the cell free zone of weil beneath the odontoblast and this plexus is know as sub odontoblastic plexus of raschkow
nerve bundles entering pulp contains what nerves
sensory afferent nerves of trigeminal (fifth cranial nerve) sympathetic branches from superior cervical ganglion
3 points that explain dentinal sensitivity
- dentine has nerve endings that are stimulated by a stimulus
- odontoblast serve as receptors that are coupled with nerves in pulp
- tubular nature of dentine permits fluid to flow in the tubules when stimulus is applied.
hydronamic hypothesis is
fluid movement through the tubules disrupts the pulpal environment, and sensed by free nerve endings in the plexus of raschkow
what are pulp stones
calcified max containing calcium-phosphorus maybe singular or multiple found on the orifice or root canal
histologically pump stones have
concentric layer of mineralized tissue formed by surface accretion around thombi, dying or dead cells or collagen fibers.
significance of pulp stones
they are a hindrance for treating pulp diseases during endodontic treatment because they decrease the overall number of cells in pulp
