Oral Histology Final Review

Question 1

What’s the name of the canal where the developing tooth is signaled to erupt through?

Answer 1

Gubernacular canal

Question 2

Most dense tissue that is mineralized?

Answer 2

Enamel

Question 3

Least dense tissue that is mineralized?

Answer 3

Cementum

Question 4

In bones, what lays down tissues?

Answer 4

Osteoblasts

Question 5

In bones, what breaks bone down?

Answer 5

Osteoclasts

Question 6

What happens during embryology morphogenesis when a blastula goes into the 4th week of morphogenesis?

Answer 6

Induction, and round/identical cells become specialized

Question 7

Neural crest cells and other brain system structures come from which layer?

Answer 7

Ectoderm

Question 8

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?

Answer 8

Hypoglossal nerve

Question 9

What are three stages of tooth development?

Answer 9

Bud, cap, and bell

Question 10

During the cap stage of tooth development, external/ outer enamel epithelium and inner enamel epithelium
meet and form what structure?

Answer 10

The Hertwig root sheath

Question 11

What is between the other enamel epithelium and inner enamel epithelium?

Answer 11

Stellate reticulum

Question 12

Just below where cementum meets enamel and the space between cementum and
dentin there is a granular layer present. What ‘s the name?

Answer 12

Tome’s layer

Question 13

In dentin, if you take a cross- section, there are tubules. What do they tell you?

Answer 13

They are highly vascular

Question 14

What’s the name of the cells in tubules that are in the cross-section in dentin?

Answer 14

Odontoblasts

Question 15

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?

Answer 15

Perikymata

Question 16

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?

Answer 16

Tome’s process

Question 17

Brain grows until the age of 6 and after that glial cells increase in number and then they
die. What kills it?

Answer 17

Apoptosis

Question 18

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?

Answer 18

Interrod enamel

Question 19

For a mature tooth, during the cementum enamel interface, what is the portion of the
root covered in cementum?

Answer 19

Radicular portion

Question 20

Root canal terminated into bottom of root, which is called what?

Answer 20

The apical foramen

Question 21

What stimulates tertiary dentin?

Answer 21

Trauma or bacterial infection

Question 22

When does primary dentin develop?

Answer 22

“Very early on”

Question 23

When does secondary dentin develop? (trick question)

Answer 23

It is present throughout life

Question 24

Dentin comes from what tissue?

Answer 24

Dental papilla

Question 25

Dental lamina sits on the Meckel’s cartilage; what is the name of the tissue around
it?

Answer 25

Dental follicle

Question 26

When taking an XR of the jaw, there is a dense bone that lines the socket. What is it’s name?

Answer 26

Lamina dura

Question 27

What is the primary tissue type of periodontal ligament (PDL) that attaches into cementum and alveolar bone
by little fibers?

Answer 27

Sharpey’s fibers

Question 28

In what way are Sharpey’s fibers oriented?

Answer 28

All different directions

Question 29

Alveolar bone sits on top of the cortical bone. What surrounds it?

Answer 29

A gomphosis joint and PDL

Question 30

What is Hertwig epithelial root sheath?

Answer 30

It forms the root of the tooth

Question 31

What does the Hertwig epithelial root sheath do?

Answer 31

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.

Question 32

What four factors comprise the periodontium?

Answer 32

1. Gingiva
2. PDL
3. Cementum
4. Alveolar bone

Question 33

What is the type of joint that the tooth joins the bone called?

Answer 33

Gomphosis

Question 34

What is sensory innervation of the tooth?

Answer 34

CN #5 trigeminal nerve

Question 35

Plexus of nerve that goes into the tooth?

Answer 35

Subodontoblastic plexus of Raschkow

Question 36

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?

Answer 36

Neonatal lines

Question 37

What is the name of the mineralized tissue that surrounds the radicular part of the root?

Answer 37

Hertwig epithelial root sheath

Question 38

What tissue does the neural crest cell migrate into?

Answer 38

Mesoderm

Question 39

What’s the unmineralized form of bone?

Answer 39

Osteoid

Question 40

What’s the unmineralized matrix for dentin?

Answer 40

Predentin

Question 41

In Cleidocranial dysplasia, the ectoderm/NCC did not migrate to the right place. What effects will the patient have?

Answer 41

Either anodontia (no teeth) or have supernumerary teeth

Question 42

There are different fields in mouth; incisor, canine, premolar fields. Problem with tooth
usually occurs in which pattern?

Answer 42

Distal before mesial
Lateral before central incisor
Premolar 2 before premolar 1

Question 43

How many deciduous teeth do we have?

Answer 43

20

Question 44

If extra cusp/ cusp of Carabelli is present, which tooth will it most likely be?

Answer 44

The first molar in the maxilla

Question 45

Where does the PDL come from?

Answer 45

Fibroblasts

Question 46

What is the function of PDL?

Answer 46

It connects the cementum to the alveolar bone