Dental Embyrology Flashcards
(33 cards)
What are the stages of dental embryology?
- Crown development
2. Root development
What makes up crown development?
- Bud
- Cap
- Bell
- Crown
How do teeth develop?
As a result of the interaction between infolding of the ectoderm (the dental lamina) and the underlying mesenchymal neural crest
What are the ectodermal proliferations termed as?
Placodes
What are the buds?
As the tissues extend deeper into the mesenchyme, they become more organised and become the dental buds
What is the cap?
When the bud starts to take a dome-like structure over the dental papilla
What is the bell?
A two layered structure of ectodermal tissues
- The outer enamel epithelium
- The inner enamel epithelium
What is the function of the OEE?
To form a protective layer over the dental organ
What is the function of the IEE?
To form the ameloblast
What do the ameloblast produce?
Enamel
What is the stellate reticulum?
A layer of loose reticular cells that are enclosed by the IEE and OEE
What is the function of the stellate reticulum?
Cushioning and protecting the dental organ; and allowing vascular fluids to reach the underlying tissues
What is the stratum intermedium?
The area between the stellate reticulum and the IEE
What is the dental papilla?
The area of differentiating mesenchyme over which the Dental Cap or Bell sites
Which part of the above is the primordial pulp tissue of the tooth?
The dental papilla
What is the Rests of Serres?
Ectodermal remnants that remain in the mesenchymal tissues after the dental lamina fragments
How are pre-ameloblasts formed?
When the cells of the IEE at the area of the Stratum Intermedium become taller
How are odontoblasts formed?
The peripheral cells of the dental papilla become cuboidal or low columnar and become odontoblasts
What do the odontoblasts form?
The secrete a mucopolysaccharide ground substance and collagen fibres
Why to the pre-ameloblasts change form?
Due to a change in nutritional supply
How are ameloblasts form?
The nucleus of the pre-ameloblasts move outwards towards the Stratum Intermedium, and they develop into ameloblasts
What do the ameloblasts form?
They secrete enamel matrix
What is the cervical loop?
At the cervical margin, the OEE and IEE are adjacent, which becomes known as the cervical loop
What is Hertwig’s Root Sheath?
As the cervical loop grows down into the mesenchyme, it becomes known as Hertwig’s Root Sheath
