Oral Histology Final Review Flashcards
What’s the name of the canal where the developing tooth is signaled to erupt through?
Gubernacular canal
Most dense tissue that is mineralized?
Enamel
Least dense tissue that is mineralized?
Cementum
In bones, what lays down tissues?
Osteoblasts
In bones, what breaks bone down?
Osteoclasts
What happens during embryology morphogenesis when a blastula goes into the 4th week of morphogenesis?
Induction, and round/identical cells become specialized
Neural crest cells and other brain system structures come from which layer?
Ectoderm
The muscles of the tongue have to migrate from back of the neck and during
this event, tongue brings nerve along. Which nerve is it?
Hypoglossal nerve
What are three stages of tooth development?
Bud, cap, and bell
During the cap stage of tooth development, external/ outer enamel epithelium and inner enamel epithelium
meet and form what structure?
The Hertwig root sheath
What is between the other enamel epithelium and inner enamel epithelium?
Stellate reticulum
Just below where cementum meets enamel and the space between cementum and
dentin there is a granular layer present. What ‘s the name?
Tome’s layer
In dentin, if you take a cross- section, there are tubules. What do they tell you?
They are highly vascular
What’s the name of the cells in tubules that are in the cross-section in dentin?
Odontoblasts
Striae of Retzius lays down enamel on the surface of the tooth from the inside. What is the
name of the external surface on the tooth?
Perikymata
When laying down enamel, processes that come out which look like picket fence that lay
protein on side and hydroxyapatite on the other side are called what?
Tome’s process
Brain grows until the age of 6 and after that glial cells increase in number and then they
die. What kills it?
Apoptosis
Enamel was thought to look like prisms but it looks like rods when it’s laid down. What
connects enamel rod to other enamel rod?
Interrod enamel
For a mature tooth, during the cementum enamel interface, what is the portion of the
root covered in cementum?
Radicular portion
Root canal terminated into bottom of root, which is called what?
The apical foramen
What stimulates tertiary dentin?
Trauma or bacterial infection
When does primary dentin develop?
“Very early on”
When does secondary dentin develop? (trick question)
It is present throughout life
Dentin comes from what tissue?
Dental papilla
Dental lamina sits on the Meckel’s cartilage; what is the name of the tissue around
it?
Dental follicle
When taking an XR of the jaw, there is a dense bone that lines the socket. What is it’s name?
Lamina dura
What is the primary tissue type of periodontal ligament (PDL) that attaches into cementum and alveolar bone
by little fibers?
Sharpey’s fibers
In what way are Sharpey’s fibers oriented?
All different directions
Alveolar bone sits on top of the cortical bone. What surrounds it?
A gomphosis joint and PDL
What is Hertwig epithelial root sheath?
It forms the root of the tooth
What does the Hertwig epithelial root sheath do?
The inner and outer epithelium of the root sheath join at the cervical junction and form a root sheath that later turns into the root.
What four factors comprise the periodontium?
- Gingiva
- PDL
- Cementum
- Alveolar bone
What is the type of joint that the tooth joins the bone called?
Gomphosis
What is sensory innervation of the tooth?
CN #5 trigeminal nerve
Plexus of nerve that goes into the tooth?
Subodontoblastic plexus of Raschkow
When laying down enamel and dentin, Straie of Retzius forms the enamel, dentin is laid
in the form of tubules. During birth, enamel in cross section can tell the age of the kid.
What is the name of the line on dentin called?
Neonatal lines
What is the name of the mineralized tissue that surrounds the radicular part of the root?
Hertwig epithelial root sheath
What tissue does the neural crest cell migrate into?
Mesoderm
What’s the unmineralized form of bone?
Osteoid
What’s the unmineralized matrix for dentin?
Predentin
In Cleidocranial dysplasia, the ectoderm/NCC did not migrate to the right place. What effects will the patient have?
Either anodontia (no teeth) or have supernumerary teeth
There are different fields in mouth; incisor, canine, premolar fields. Problem with tooth
usually occurs in which pattern?
Distal before mesial
Lateral before central incisor
Premolar 2 before premolar 1
How many deciduous teeth do we have?
20
If extra cusp/ cusp of Carabelli is present, which tooth will it most likely be?
The first molar in the maxilla
Where does the PDL come from?
Fibroblasts
What is the function of PDL?
It connects the cementum to the alveolar bone
