Pulp

Question 1

What are 5` functions of dental pulp?

Answer 1

1. Inductive - Initiates tooth formation
2. Formative - Odontoblasts surround pulp
3. Protective - Responds to stimuli
4. Nutritive - Carries oxygen and nutrients to tooth
5. Reparative - Formation of tertiary dentin

Question 2

What tissue type is the dental pulp?

Answer 2

Specialised loose CT

Question 3

Where is the dental pulp derived from?

Answer 3

Dental papilla

Question 4

Where is dental pulp found?

Answer 4

Pulp chamber and root canals of the tooth

Question 5

What are the 2 anatomical regions of the pulp?

Answer 5

1. Coronal Pulp

2. Radicular Pulp

Question 6

Where is the coronal pulp found?

Answer 6

The crown of the tooth

Question 7

What are the 6 surfaces of the coronal pulp?

Answer 7

1. Mesial
2. Distal
3. Buccal
4. Lingual
5. Occlusal
6. Floor

Question 8

Where is radicular pulp found?

Answer 8

Root of the tooth

Question 9

From the outermost layer to the innermost layer, what are the 4 histological zones of the dental pulp?

Answer 9

1. Odontoblastic zone
2. Cell-free zone
3. Cell-rich zone
4. Pulp core

Question 10

Name 4 cell types found in the pulp

Answer 10

1. Odontoblasts
2. Fibroblasts
3. Undifferentiated mesenchymal cells
4. Defence cells

Question 11

What is the function of fibroblasts?

Answer 11

Make the matrix components of pulp i.e. fibres and ground substance

Question 12

Where are fibroblasts found?

Answer 12

Cell-rich zone

Question 13

What is the function of undifferentiated mesenchymal cells?

Answer 13

Pools of cells from which new odontoblasts or fibroblasts can be derived

Question 14

What are 4 components of the pulp matrix?

Answer 14

1. Fibres
2. Glycosaminoglycans
3. Proteoglycans
4. Glycoproteins

Question 15

What 2 things make up the fibres found in the pulp matrix?

Answer 15

1. Collagen Type I

2. Collagen Type II

Question 16

Name 3 GAGs found in the pulp matrix?

Answer 16

1. Hyaluronic acid
2. Dermatan sulphate
3. Chondroitin sulphate

Question 17

What are proteoglycans?

Answer 17

Protein core and a GAG

Question 18

What are the 3 levels of vascular supply to the pulp?

Answer 18

1. External carotid arteries
2. Superior and inferior alveolar arteries
3. Pulpal arterioles

Question 19

Where are most of the nerve ends found in the dental pulp?

Answer 19

Odontoblasts, cell-free zone or dentinal tubules

Question 20

What is the nerve plexus of the crown found beneath the odontoblasts?

Answer 20

Plexus of Raschkow

Question 21

What are 4 ways hypersensitivity of the pulp can be triggered?

Answer 21

1. Temperature
2. Mechanical pressure
3. Chemical exposure
4. Dehydration

Question 22

What were the 3 theories put forward to explain sensitivity?

Answer 22

1. Direct innervation
2. Transduction
3. Hydrodynamic

Question 23

What is the direct innervation theory?

Answer 23

Nerve fibres extend through entire dentinal tubule and directly transmit pain

Question 24

What is the transduction theory?

Answer 24

Odontoblasts act as receptors for pain and transmit signal to nerves

Question 25

Why is the direct innervation theory wrong?

Answer 25

Plexus of Raschkow is not mature until complete tooth eruption

Question 26

Why is the transduction theory wrong?

Answer 26

No synapse is found between odontoblasts and nerves

Question 27

What is the hydrodynamic theory?

Answer 27

Stimuli cause movement of dentinal fluid which causes depolarisation of nerve endings at dentin-pulp interface

Question 28

How does cold and chemical stimuli cause dentinal fluid to move?

Answer 28

Outward flow of fluid

Question 29

How does mechanical and hot stimuli cause dentinal fluid to move?

Answer 29

Inward flow of fluid

Question 30

What are 4 age-related changes to pulp?

Answer 30

1. Pulp is small 2. Pulp is less vascular 3. Pulp is more fibrous 4. Pulp is less innervated

Question 31

What are pulp stones?

Answer 31

Round calcified masses which appear in root canal or coronal portions of pulp

Question 32

What is the main cause of pulp stones?

Answer 32

Aging

Question 33

What are 2 types of pulp stones?

Answer 33

1. True denticles | 2. False denticles

Question 34

What does a true denticle resemble?

Answer 34

Dentin

Question 35

What does a false denticle resemble?

Answer 35

Bone

Question 36

What are 3 major clinical considerations with regards to dental pulp?

Answer 36

1. Pain from other sites can radiate to here e.g. angina 2. It is sensory so requires anaesthesia during cavity preparation 3. Pain in pulp is difficult to localise