Module 3-4 Flashcards
What is odontogenesis?
The process of tooth development 
What are the two dentitions called? 
Primary dentition and permanent dentition
How many teeth does the primary dentition contain? 
20 
How many teeth does the permanent dentition contain? 
32
 Odontogenesis of the primary dentition begins in what week of prenatal development?
Six and seven of embryonic period.
After initiation of odontogenesis what are the three stages in tooth development? 
Bud stage
Cap stage
Bell stage
After the bell stage, what stage occurs?
Apposition stage
What physiologic processes occur during odontogenesis?
 induction, proliferation, differentiation, morphogenesis, and maturation
What is induction?
The action of one group of cells on another.
This lead to establishment of a developmental pathway in tissues.
What is proliferation? 
Controlled cellular growth, and accumulation of byproducts.
What is differentiation? 
The change in identical embryonic cells to become distinct cells.
What is morphogenesis? 
Development of specific tissue structure 
What is the first stage of tooth development?
The initiation stage 
During the initiation stage, the outer part of the ectoderm gives rise to ____
 oral epithelium
Ectomesenchyme is derived from what cells
Neural crest cells (NCCs)
What separates oral epithelium and the ectomesenchyme?
The basement membrane
What forms of dental lamina?
Oral epithelium grows into the ectomesenchyme and is induced.
What does a dental placode consist of?
Thickened epithelium with an underlying neural crest derived from mesenchyme or neuroectoderm.
Lack of initiation within the dental lamina results in what developmental disturbance?
Anodontia
What is anodontia?
The absence of teeth
Supernumerary teeth are also called ______
Hyperdontia
When does the bud stage occur?
The beginning of the eighth week of prenatal development
Ectomesenchyme surrounds the ______ in the bud stage.
Dental lamina
What is macrodontia?
What is microdontia?
Macrodontia = abnormally, large teeth
Microdontia = abnormally small teeth
When does the cap stage occur?
Between the ninth and 10th week of prenatal development, or during the fetal period.
What is primordium?
The tooth germ
During what stage does primordium occur?
The cap stage
What are the three components of the tooth germ?
Enamel organ
Dental papilla
Dental sac
What does the dental papilla produce?
Dentin and pulp
What will the dental sac produce?
Cementum
Periodontal ligament
Alveolar process
What does succedaneous mean?
Teeth that have permanent teeth growing under them.
Which teeth are considered succedaneous
Anterior teeth and premolars.
What are non-succedaneous teeth?
Teeth that have no primary predecessors.
Which teeth are considered non-succedaneous?
Permanent molars
When does the bell stage occur?
Between the 11th and 12th week of prenatal development
What are the four different types of cells found within the enamel organ during the bell stage?
Outer Enamel epithelium
Stellate reticulum
Stratum intermedium
Inner enamel epithelium
The outer cuboidal cells of the enamel organ are called what?
Outer enamel epithelium (OEE)
What is the purpose of the outer enamel epithelium?
It serves as a protective barrier during an enamel production
The innermost columnar cells of the enamel organ are called
Inner enamel epithelium (IEE)
Inner enamel epithelium turn into enamel secreting cells called
Ameloblasts
What does the opposition stage form?
Mineralized dental tissue
Enamel
Dentin
Cementum
What is the first signal for tooth development?
Dental placodes
Dens en Dente occurs during what stage of development?
Cap stage
What are tubercles?
Enamel extensions forming extra cusps
What occurs in the bell stage?
Odontoblasts make dentin
IEE creates enamel
What type of cell is the outer enamel epithelium?
Cuboidal
What type of cells are inner enamel epithelium?
Cuboidal
Inner enamel epithelium differentiates into enamel secreting cells called
Ameloblasts
What stage of odontogenesis does the connection between surface epithelium and the tooth germ disintegrate?
Late bell stage
What is amelogenesis?
The production of enamel
Where is the tomes process located?
Ameloblast
(Picket fence)
What is the function of Tomes Process?
Secretion of enamel matrix
Where are the dentinal tubules found
End of Odontoblasts
Enamel can only be made during
Initial tooth development
What structure is responsible for root formation?
Cervical loop
Epithelial rests of Malassez become stuck where
PDL and Cementum
What creates cementum?
Cementocytes
What does the Sharpeys fibers connect?
PDL and alveolar bone
The crown seen above the gumline id called the
Clinical crown
The whole crown is called the
Anatomical crown
Enamel has masticatory impact of ____ pounds of pressure per tooth
20-30
What makes up the color of enamel?
Dentin
Erosion can be caused from
Bulimia
GERD
What pH causes acid to form resulting in destruction of tooth surface enamel?
5.5 or lower
Enamel rods that curve from the right and left are called
Hunter-Schreger bands
Where is gnarled enamel found?
Cusps of teeth
Where is the interrod enamel found
In between enamel rods
What are Incremental lines of Retzius
Bands that cross enamel rods.
Layers enamel as it is forming
What are enamel spindles
Odontoblasts that cross over into enamel and get trapped by enamel formation
What are the two stages of dentin maturation?
Primary
Secondary
What is the lifeline of the tooth?
Dentinal tubules
Predentin consists of _____
Nonmineralized collagen fibers
Where is mantle Dentin found?
Upper section of dentinal layer
When is primary dentin formed?
Before the apex of the tooth is formed
When is secondary dentin formed?
Constantly throughout the tooth life
When is tertiary dentin found?
After tooth trauma
Where are vonKorffs fibers found?
Perpendicular to mantle dentin (opposite)
What type of dentin makes up the bulk of dentin?
Circumpulpal dentin
When does circumpulpal dentin form?
Forms and matures after mantle dentin
