Pulp and Cementum (UNIT 4) Flashcards
What is the pulp of a tooth derived from?
ectomesenchyme of the dental papilla.
Bud stage
Dental lamina ectoderm grow into neural crest/ ectomesenchyme.
Cap stage
Histodifferentiation.
Bell stage
Cytodifferentiation, Morphodifferentiation
Crown stage
When hard tissue is laid down: Dentin and then Enamel.
When the Dental Pulp Organ forms from the dental papilla.
What is the only nonmineralized tissue of the tooth?
The pulp
What is the texture of pulp tissue?
Soft and gelatinous.
How does the size and elasticity of pulp change with age?
The pulp is larger and more elastic in young teeth compared to older teeth.
What happens to the pulp as a tooth ages?
the pulp is reduced in size by the deposition of secondary dentin.
How is pulp produced during a person’s life?
- produced rapidly during tooth development
- slowly during adult life
- and rapidly in response to injury.
How does the volume of pulp vary across different types of teeth?
Molars have more pulp than incisors.
What is the formative function of the pulp?
- supports and houses odontoblasts
- plays a major role in dentin production
- including the formation of tertiary dentin in response to injury.
What is the sensory function of the pulp?
Innervation of the tooth; providing sensory function, including the sensation of pain and temperature changes
What is the nutritive function of the pulp?
provides nutrition to all the organic components of the mineralized tissue
What is the defensive function of the pulp?
responds to injury and infection through an inflammatory response
What cells are involved in the formative function of the pulp?
Odontoblasts
Fibroblasts
Ectomesenchymal stem cells
Which nerve fibers are involved in the sensory function of the pulp?
nerve fibers from branches of the trigeminal nerve.
What blood vessels provide nutrition to the pulp?
superior and inferior alveolar arteries and veins.
Which cells are involved in the defensive function of the pulp?
- white blood cells (lymphocytes and neutrophils)
- macrophages
- mast cells.
What is the role of blood vessels in the pulp?
supply nutrients and oxygen to odontoblasts
Through which structure do blood vessels enter and leave the pulp?
via the apical foramen
which structure does the pulp share blood supply with?
the periodontium, which can allow bacterial infections to spread from the periodontal ligament.
What is the role of unmyelinated C fibers in the pulp?
- respond to inflammation and toxins
- causing prolonged, dull/aching, poorly localized pain that lasts longer than the applied stimulus.
What is the role of myelinated fibers (Alpha type) in the pulp?
- extend into the dentinal tubules
- give rise to brief, sharp, well-localized pain in response to thermal, evaporative, tactile, osmotic, or chemical stimuli.
Why is the sensory innervation of the pulp important during cavity preparation?
is why analgesics (pain relievers) are necessary during cavity preparation to manage pulpal pain.
How can pulp inflammation affect the pain felt by the patient?
can be extremely painful or have no associated pain, depending on the state of the nerves within the pulp.
What happens to the tooth if the pulp becomes necrotic and how does it appear?
- the presence of dead tracts in the dentin, caused by the death of odontoblasts.
- the crown of the tooth may appear darker
What do the unmyelinated Autonomic supply?
smooth muscle of the blood vessels to regulate blood flow.
Where is the coronal pulp located?
in the crown of the tooth.
What structures may the coronal pulp contain?
a roof, pulp horns, and a floor.
Where is the radicular pulp located?
in the root canal of the tooth.
What is the shape of the radicular pulp?
tube-shaped.
How is the radicular pulp connected to the periodontal connective tissue?
it is continuous with the periodontal connective tissue at the apical foramen.
What is the function of the odontoblastic layer in the pulp?
Synthesize and secrete dentin
Does the odontoblastic layer have sensory nerves?
Yes
What happens in the odontoblastic layer in response to bacterial toxins?
Produce pro-inflammatory mediators
Where is the cell-free zone (of Weil) located?
in the coronal pulp.
What is found in the cell-free zone (of Weil)?
- extracellular matrix
- nerve fibers
- capillaries
- tissue fluid
What types of cells are found in the cell-rich zone of the pulp?
fibroblasts and ectomesenchymal stem cells, which can differentiate into odontoblasts.
What structure is found in the cell-rich zone besides cells?
Nerve plexus
What is the pulp core?
bulk of the pulp and is continuous with the periodontal ligament (PDL).