REVIEW NOTES: DENTAL EMBRYOLOGY
—--------------------------------------------------------------------------------------------------------------------------
Part one: Prenatal Development Notes and Review Questions
—----------------------------------------------------------------------------------------------------
1
, Dental Embryology_Papers of Dentistry
Prenatal Development
Prenatal development is categorized into three primary periods, each
characterized by specific biological events that influence embryo and fetus
formation.
Preimplantation period: first week
Embryonic period: 2-8 week
Fetal period: 3-9 months
Prenatal development begins with pregnancy until childbirth.
These periods align with the pregnancy trimesters.
Pre-implantation and embryonic: First trimester.
Fetal period: Second and third trimesters.
Primordium refers to the initial identifiable phase of organ or tissue
formation. It consists of the simplest collection of cells that can evolve into
complete organs in the adult stage.
—----------------------------------------------------------------------------------------------------
What are the two primary layers of a blastocyst, and what future structures
do they form?
The blastocyst comprises two primary layers: the trophoblast, which constitutes the
outer layer and is responsible for forming structures that support prenatal development.
The internally located embryoblast differentiates into the embryo itself.
2
, Dental Embryology_Papers of Dentistry
Note: During fertilization, the zona pellucida undergoes immediate chemical changes
to prevent polyspermy (the entry of additional sperm into the egg).
3
, Dental Embryology_Papers of Dentistry
Based on this diagram, the developmental sequence progresses as follows:
Clinical Considerations related to prenatal development
As future dental hygienists or dentists, you should be aware of some of the main clinical
cases that occur during prenatal development. You may encounter such situations
during your career!
4