Week 6 Flashcards
(17 cards)
What is odontogenesis?
The stem cell communication that ultimately results in teeth
Odontogenesis involves various stages of tooth development and eruption.
List the stages in tooth development.
- Formation of Dental lamina
- Bud Stage
- Cap Stage
- Bell Stage
- Crown Formation
- Root Formation
When does the odontogenesis of the primary dentition begin?
Around the sixth week
This process starts with the formation of the dental lamina.
What does the ectoderm lining the stomodeum give rise to?
Oral epithelium
This epithelium thickens to form the dental lamina.
What occurs during the Bud Stage?
Extensive proliferation of the dental lamina to form oval shaped masses (buds)
This stage occurs at about 8 weeks.
What characterizes the Cap Stage?
Uneven proliferation resulting in a cap shape attached to the dental lamina
This stage occurs between weeks 9 and 10.
What is the significance of the Bell Stage?
Characterized by significant histodifferentiation and formation of distinct components of the enamel organ
This stage occurs between weeks 11 and 12.
What are the components of the enamel organ?
- Outer enamel epithelium (OEE)
- Inner enamel epithelium (IEE)
- Stellate reticulum
- Stratum intermedium
What is the primary function of the Outer Enamel Epithelium?
Serve as a protective barrier for the enamel organ
What do the cells of the Inner Enamel Epithelium differentiate into?
Ameloblasts that form the enamel matrix
What is the role of the Stratum Intermedium?
Supportive in the production of the enamel matrix
What does the Stellate Reticulum secrete?
Hydrophilic ground substance which pulls water into the dental organ
This creates the classic “star” shape of these cells.
What occurs during the Crown & Root Formation stages?
Production of enamel, dentine, and cementum in root formation
Maturation times vary significantly from tooth to tooth.
What does Hertwig’s root sheath induce?
Differentiation of underlying mesenchymal cells to form odontoblasts
It maps out the anatomy of the root.
What happens to the root sheath remnants after dentine development?
Remain as islands of cells known as Epithelial rests of Malassez
What is the role of the reduced enamel epithelium (REE) during tooth eruption?
Fuses with the oral mucosa and breaks down to create a canal for tooth eruption
This process involves peeling back of the cellular layer on the crown.
Fill in the blank: The cervical loop grows further down to form _______.
Hertwig’s root sheath
