Lec 3 Flashcards
(24 cards)
necrosis travels which direction
coronal to apical
what is the pulpal organ
central mass of tooth made of soft tissue, sensory innervations vessels/lymphactics
odontoblasts and fibroblasts
most common cell in pulp?
fibroblasts
primary function of pulp?
formative: odontoblasts form dentin
ameloblasts form enamel
secondary functions of pulp?
support, protection, sensation, defense, repair
what are fibroblasts?
most common cell in pulp, basic cell in all CT
arise from ectomesenchymal cells
form type I and III collagen and ground substance
important for regeneration in wound healing
what are odontoblasts?
cell in pulp responsible for dentinogenesis
also important in amelogenesis
produce collagen fibers and proteoglycan matrix (become mineralized dentin)
processes extend into dentin tubules
when does sclerotic dentin form?
when bacteria invade the pulp
how is tertiary dentin formed differently
formed by fibroblasts in response to trauma
-has no dentinal tubules
what is the Hydrodynamic Theory for tooth sensitivity
anything that causes movement of the fluid in the dentinal tubules causes pain/sensitivity in the pulp
what is the lamina dura
cortical bone around tooth, thin layer
white line on radiograph
when does primary dentin form?
as the roots of teeth develop, young patients
when does secondary dentin form
after tooth eruption
what happens to the pulp as we age
secondary dentin deposition as we age
reduces the size of the pulp uniformly, but retains the general form of the pulp
(tertiary dentin will change shape of pulp!)
what is pulp canal obliteration PCO?
(also called calcific metamorphosis)
Pulp sclerosis, a combo of secondary and tertiary dentin formation in response to chronic injury.
Occurs before pulp becomes necrotic, must be vital to occur.
Canal is blocked, refer to advanced endo
what are the 4 common etiologies of pulp irritation?
microbiological
mechanical
chemical
trauma
what amount of dentin must cover the pulp to remain healthy
0.5 mm of dentin covering pulp keeps it healthy
many etiologies of pulp are what type of cause?
iatrogenic (bur heating up pulp)
what is the #1 cause of pulp irritation?
microbiological
dental caries is the #1 threat to the pulp
what are the portals of access for MO to enter the pulp (5)
caries/leaking restoration (most common!)
cracked or fractured teeth
cemental defect at CEJ
open dentinal tubules
perio invasion into apex (deep pocket)
what are some examples of mechanical irritation of the pulp
iatrogenic:
cutting w/o coolant
aspiration of odontoblasts into tubules (occurs when dentin overheats)
PULP CANNOT TOLERATE HEAT!! (10 degrees)
excessive drying w/ air
dessicants (alocohol, chloroform)
polishing
pulp exposure
use of laser
trauma to the pulp can include?
external: falls and sports accidents
internal: habits like bruxism
if the pulp is vital, what will Pt feel during cold testing?
pain! Vital pulp still has sensitivity
if pain lingers, sign that RC is needed
no pain = necrotic pulp
when is tertiary dentin deposited?
deposited over area of injury by fibroblasts
attempt to repair, protect, or insulate pulp from more injury
form/shape of pulp is changed
