Module 1: Reading Assignment 1: Pulp Biology Flashcards
What is the embryonic cell structure that the tooth buds form from?
Oral epithelium
What is formed when the oral epithelium invaginates
Dental Lamina
After the epithelial based bud has formed, what types of cells begin to condense around it?
Ectomesenchyme Cells
What embryonic structure do ectomesenchyme cells come from?
Neural Crest
When the bud invaginates, what developmental stage has been reached?
Cap
What is the name of the bell shaped structure in the Bell stage?
Enamel organ
What does the ectomesenchymal tissue inside the invagination of the enamel organ eventually become?
The pulp
What is the name of the future pulp tissue while it is in the bell stage?
Dental Papilla
During the bell stage, what do the inner layer of enamel organ cells become?
Ameloblasts
During the bell stage, what do the cells of the outer layer of the dental papilla differentiate into?
Odontoblasts
During which stage do odontoblasts begin to deposit dentin?
Bell Stage
Once dentin is deposited by the odontoblasts, what is the dental papilla officially known as
the Dental Pulp
After the pulp is formed, a layer of cells forms around the enamel organ and the pulp….what is it called
Dental Follicle
What does the dental follicle eventually become?
The periodontal attachment
Several genes control the histodifferentiation of cells during embryonic development of the teeth, what are 3 developmental defects that can occur due to gene expression disorders at this stage of development?
Anodontia
Amelogenesis imperfecta
Odontogenesis imperfecta
From what cells do odontoblasts arise from?
Undifferentiated ectomesenchyme cells
What cells interact with the ectomesenchyme cells in order to stimulate them to differentiate into odontoblasts?
The ectodermal cells of the Inner Enamel Epithelium (Enamel Organ)
When the odontoblasts have completed their differentiation what part of the enamel organ disappears?
The basal lamina which contained the cells stimulating the odontoblast’s differentiation
Odontoblasts are joined together in a “line” due to what types of connections?
Tight Junctions
Desmosomes
Gap
The newly matured and linked odontoblasts are ready to do what?
Deposit dentin
The deposition of enamel signals the ameloblasts in the IEE of the enamel organ to do what?
Start depositing enamel
At what end of the tooth does unmineralized dentin deposition begin?
At the cusp tip, moving in an apical direction
What circumstance determines the shape of the crown of the future tooth?
The genetically predetermines proliferation pattern of the cells in the Inner Enamel Epithelium
What is the first thin layer of dentin that is deposited called?
Mantle Dentin
How does mantle dentin differ from Circumpulpal dentin?
The direction and size of the collagen fibers
What is predentin, and where is it located
It is unmineralized dentin located immediately next to dentinal layers
Does dentin formation ever stop?
No, but its rate slows with age
What can increase the rate of dentin formation?
The presence of a toxic insult that has invaded the dentin
What is the name of the point where the IEE and OEE meet?
The Cervical Loop
The cervical loop demarcates the border between what two future tissue layers?
Crown and Root
What is the name of the structure that arises from the cervical loop and initiates root formation
Hertwigs Epithelial Root Sheath
How does the root sheath actually help “build” the root?
It stimulates odontoblasts
What determines the shape of the root structure
The genetically determined pattern of proliferation of the root sheath cells
How do multiple roots form
When opposing parts of the root sheath proliferate vertically and horizontally
What is formed by opposing horizontal segments of the root sheath
The epithelial diaphragm which results in a single root tooth
If the root sheath stimulates odontoblasts, how does cementum get formed?
Once the first dentin of the root has been laid down, the root sheath’s basement membrane breaks down and inner sheath cells secrete hyaline over the new root dentin.
After that the root sheath breaks down and allows dental follicle cells to contact the new root dentin and become cementoblasts
The new cementoblasts will deposit what subtype of cementum?
Acellular
This acellular cementum will serve as the achor material for what tissue
principal fibers of the PDL
When epithelial remnant of the root sheath get caught in the PDL, what are they called?
Epithelial rest cells of Malassez