Final Review from 11/9/17

Question 1

The gubernacular cord is a thin connective tissue that goes from where to where?

Answer 1

From the oral epithelium to the tooth follicle

Question 2

What is the function of the gubernacular cord?

Answer 2

It is the pathway for tooth eruption

Question 3

Name the 3 hard tissues that make up the tooth

Answer 3

1. Enamel (from ectoderm)
2. Cementum
3. Dentin (from ectomesenchyme)

Question 4

What’s the origin of osteoblasts?

Answer 4

They come from ectomesencyme, which is from the neural crest

Question 5

Where do osteoclasts come from?

Answer 5

They come from monocytes, which are hematopoietic cells

Question 6

What’s the process called where you turn ectoderm into ectomesenchyme?

Answer 6

Epithelial-mesencymal transformation (EMT, histodifferentiation)

Question 7

What tissue do NCCs come from?

Answer 7

Ectoderm

Question 8

What are the two structures in the head that are not made from ectomesenchyme?

Answer 8

Enamel and occipital bone

Question 9

Where does enamel come from?

Answer 9

Ectoderm

Question 10

What nerve supplies the motor supply of the tongue?

Answer 10

CN 12, hypoglossal nerve

Question 11

What CN supplies the anterior 2/3 of the sensation of the tongue?

Answer 11

CN 5, trigeminal nerve (from the 1st arch)

Question 12

What nerve supplies the anterior 2/3s of the tongue for taste?

Answer 12

The chorda tympania (a branch from the facial nerve, CN VII)

Question 13

What nerve supplies the posterior 1/3 of the tongue for sensory, as well as its sense of taste?

Answer 13

CN 9, the glossopharyngeal nerve (from the 3rd arch)

Question 14

Describe the process of amelogensis (also called Tome’s process)

Answer 14

Whereby ameloblasts lay down mineralization

Question 15

What is the fundamental structure of enamel? What makes up the source?

Answer 15

Rods, made of hydroxyapatite

Question 16

What’s in the pulp?

Answer 16

Pulpal core, nerve trunks and blood vessels

Question 17

Where does the root canal terminate?

Answer 17

The apical foramen

Question 18

What forms dentin>?

Answer 18

Odontoblasts

Question 19

What’s the name of the bone that lines a tooth socket?

Answer 19

Lamina dura (also it is the alveolar bone proper)

Question 20

What’s the condition called where the tooth root fuses to the socket?

Answer 20

Ankylosis

Question 21

What is PDL made of?

Answer 21

Collagen fibers, which is CT

Question 22

What forms PDL?

Answer 22

Fibroblasts

Question 23

What ligament is associated with PDL?

Answer 23

Ectomesenchyme

Question 24

What structure attaches the periodontal ligament (PDL) to the tooth socket and the tooth?

Answer 24

Sharpey’s fibers

Question 25

What plexus of nerves serves in the tooth?

Answer 25

Trigeminal nerve (which is from the 1st branchial arch)

Question 26

The neonatal line in enamel is larger than the rest of what in the enamel?

Answer 26

The rest of the striae of Retzius