pulp and dentine

Question 1

What type of connective tissue is pulp

Answer 1

Loose connective tissue (viscous gel like substance)

Question 2

Innervation of pulp

Answer 2

Sensory (somatic Afferents)
Autonomic (sympathetic)

Question 3

5 functions of pulp

Answer 3

Nutrition (blood)
Immune defence
Growth of dentine pri and sec
Repair of dentine tertiary
Pain transmission (sensory)

Question 4

How is dentinal fluid formed

Answer 4

Leakage of fluid from pulp capillaries

Question 5

What’s the difference between between reactionary and reparative dentine

Answer 5

Reactionary - odontoblasts
Reparative - more severe, odontoblasts dead so replaced by differentiated sub-odontoblastic stem cells

Question 6

Plexus of raschow location

Answer 6

Below the cell rich layer

Question 7

Which cranial nerve innervates pulp

Answer 7

Trigeminal division 2 and 3 (maxillary and mandibular

Question 8

Dentinal tubules in which location has the highest chance of finding nerves

Answer 8

40% of cuspal dentine has nerves
15% of coronal dentine has nerves
4% of root dentine has nevees

Question 9

Inward or outward flow activates interdental nerves more?

Answer 9

Outwards because of the pressure stretching the nerves causing greater stimuli

Question 10

Type of collagen in pulp

Answer 10

Type 1 and 3
Oxytalan

Question 11

Does pulp have lymphatics

Answer 11

Yes

Question 12

What pulpal elements extend into dentine?

Answer 12

Odontoblast processes
Dentinal fluid
Immune cells
Nerve terminals

Question 13

Relationship between dentinal flow and pulp pressure

Answer 13

Proportional

Question 14

How does outward dentinal tubules fluid flow have a defence function?

Answer 14

Outwards flow temporarily keeps bacteria and harmful substances away from the pulp until other immune mechanisms step in

Question 15

6 causes of toothwear

Answer 15

Attrition
Erosion
Abrasion
Abfraction
Caries
Operative procedures

Question 16

How does tertiary dentine protect the pulp

Answer 16

Forms a plug and seals off dentinal tubules from the pulp

Question 17

What is a way to treat hypersensitivity

Answer 17

Potassium nitrate depolarizes nerves and prevents Repolarisation

Some other chemical agents also plug dentinal tubules preventing outward flow of dentinal fluid

Question 18

Is cooling and heating outward or inward flow of dentinal fluid

Answer 18

Cooling- outwards
Heating inwards

Think about cold and hypersensitivity - more activation of nerves so outwards stretching of nerves

Question 19

How does high fillings cause dentinal pain?

Answer 19

Force distorts the dentine and alters fluid flow

Question 20

Blood supply of teeth

Answer 20

External carotid -> maxillary artery -> superior alveolar artery and incisive artery (mandibular)

Question 21

Why is permeability of inner dentine higher than that of outer dentine

Answer 21

Inner dentine has more tubules and tubules of larger diameter

Question 22

Types of nerve fibres in pulp

Answer 22

A beta
A delta
C fibres

Most of the fibres inside the pulp are the tapered terminal segments of axons

Question 23

Are majority of the nerve fibres in pulp sensory or sympathetic nerves?

Answer 23

Sensory - pain

Question 24

What is the hydrodynamic mechanism of dentinal fluid

Answer 24

1 stimulus acts on exposed dentine

2 increases dentinal fluid flow

3stretches the intradental nerves and generates AP

4sends signal to brain to cause pain

Question 25

How is blood supply in pulp controlled

Answer 25

Vasoconstriction - sympathetic nervous system
Vasodilation - peptides released by peptidergic sensory afferents ( CGRP AND SUB P are potent vasodilators)

Adrenaline - hormone vasoconstriction

Dugs like local anaesthetic (vasoconstriction )

Question 26

Describe the process of neurogenic inflammation

Answer 26

Stimulation
Sensory nerve activation
Release of peptides CGRP and sub p
Vasodilation causing increased permeability of blood vessels
Influx of immune and exudate
Increased pulpal pressure and outward tubular fluid flow
More nerve activation