Care of the Pulp

Question 1

What is present in the pulp?

Answer 1

Cells
¡ Odontoblasts

Nerves (plexus of Raschkow)
¡ Alpha fibres (myelinated)
¡ C-fibres (unmyelinated)

Blood vessels

Question 2

What are the functions of the pulp?

Answer 2

Nutrition, sensory, temperature, pressure, pain, protective, reparative healing, and formative functions.

Question 3

What are possible injuries to pulp?

Answer 3

caries
cavity preparation (heat, air, vibration, cutting processes)
restorations
restorative materials (toxic, exothermic)
trauma
tooth wear
periodontal pathology
orthodontic treatment
radiation therapy

Question 4

What is RDT and what is the size?

Answer 4

remaining dentine thickness
approximately 2mm of dentin or an equivalent thickness of materials should exist to protect the pulp.

Question 5

How does dentine permeability change with cavity depth?

Answer 5

The deeper the cavity, the greater the dentine permeability due to the increase in number and size of dentine tubules.

Question 6

What are things that can enter pulp due to dentine permeability?

Answer 6

¡ Bacterial substances
¡ Enzymes
¡ Peptides
¡ Exotoxins
¡ Endotoxin (e.g. LPS)
¡ Polysaccharides
¡ Antibodies
¡ Immune complexes
¡ Complement proteins
¡ Tissue destruction products

Question 7

What are the types of dental pain and their stimulation?

Answer 7

sharp pain, stimulated by alpha fibers

dull/aching pain, stimulated by C fibers.

Question 8

What are the possible pulpal diagnosises?

Answer 8

Healthy pulp
reversible pulpitis
irreversible pulpitis
necrotic pulp.

Question 9

What are the possible periapical diagnosises?

Answer 9

Normal periapical tissues
periapical periodontitis (symptomatic/asymptomatic)
acute apical abscess
chronic apical abscess
condensing osteitis.

Question 10

What are the qualities of reversible pulpits?

Answer 10

Vital, inflamed pulp

Can reverse to health if adequate vital pulp therapy performed

Regular response to sensibility tests

Question 11

What are the qualities of irreversible pulpits and what are treatment options?

Answer 11

¡ Vital, chronic inflammation can not heal

Spontaneous pain

¡ Treatment options:
1. Pulpotomy followed by “vital pulp therapy”
1. Only if some remaining pulp tissue is not irreversibly inflamed
2. Pulpectomy then RCT
3. Extraction

Question 12

What is the difference of reversible vs irreversible pulpitis?

Answer 12

Reversible pulpitis:
Short pain to cold
Hydrodynamic expression- microleakage (A-fibres)
No change in pulp blood flow

Irreversible pulpitis:
Spontaneous pain, intermittent, sleep disturbance
Negative to cold, pain to hot (e.g. tea/ coffee) (C-fibres)
Increase in pulpal blood flow

Question 13

What is the treatment options for necrotic teeth (closed apices vs open apices)?

Answer 13

mature teeth
rct
extraction

immature teeth
pulpotomy then RCT
extraction

Question 14

What is the sensitivity of normal periapical tissues and how do they appear radiographically?

Answer 14

Not sensitive to percussion or palpation

Radiographically,: Lamina dura intact, PDL space uniform.

Question 15

symptomatic periapical periodontitis
VS
asymptomatic periapical periodontisis

Answer 15

Symptomatic Periapical Periodontitis:
* Painful, especially when biting down or chewing, hot/cold
* Develops suddenly and may worsen quickly
* X-ray may have periapical radiolucency

Asymptomatic Periapical Periodontitis:
* No pain or discomfort
* Develops gradually over time
* X-ray has apical radiolucency

Question 16

What are qualites of acute apical abscess?

inflammatory reaction to pulpal infection and necrosis

Answer 16

Rapid onset, spontaneous pain
Extreme tenderness to pressure, pain
Pus formation, swelling
Malaise, lymphadenopathy, fever

Question 17

What are the qualities of chronic apical abscess?

inflammatory reaction to pulpal infection and necrosis

Answer 17

Gradual onset
Little or no discomfort
Intermittent discharge of pus through sinus tract.
Periapical/periradicular radiolucency.

Question 18

What should be done for a chronic apical abcess?

Answer 18

Carefully place GP (gutta percha) cone into sinus tract of suspected tooth and take radiograph

Question 19

What are the qualities of condesing osteitisis?

Answer 19

diffuse radiopaque lesion
localised bone hardening to a low-grade inflammatory stimulus
usually seen at apex of tooth
no symptoms

Question 20

What are the types of sensibility tests?

Answer 20

¡ Electric pulp tests (Electric Pulp Tester (EPT))

¡ Thermal tests:
¡ Cold tests (Ethyl chloride)
¡ Heat tests (Hot gutta percha (GP))

¡ Test drilling

Question 21

What are the problems of these tests?

Answer 21

¡ These tests stimulate nerve fibres
¡ Tooth vitality is related to blood supply, not nerve stimulation
¡ Laser doppler needed to assess blood flow

¡ Periradicular inflammation occurs before pulp totally necrotic

¡ Difficulties in testing multi-rooted teeth

Question 22

What is the EPT?

Answer 22

Electric current used to stimulate sensory nerves at pulp-dentine junction
¡ A-delta fibres stimulated
¡ Unmyelinated C-fibres may or may not respond

electric pulp test

Question 23

What is the scale of EPT?

Answer 23

0 -80

if number reaches 80 and no sensation, there is a loss of vitality (necrotic)

if number is too low, the tooth is inflammed

Question 24

How do thermal tests work?

Answer 24

Believed to work by hydrodynamic forces
¡ Fluid movement in dentinal tubules (due to thermal stimulus)
¡ Activates pulp’s sensory nerve receptor units in pulp:

Question 25

What can too much heat cause?

Answer 25

irreversible pulpitis

Question 26

How do heat tests work?

Answer 26

¡ Initial stimulation of A-delta fibres
¡ Sharp pain

¡ Continued stimulation results in C-fibre activation
¡ Dull radiating pain

¡ Procedure
¡ Vaseline on tooth (gutta percha becomes sticky)
¡ Apply hot gutta percha/ green stick to tooth

Question 27

What does a negative response to a heat/ cold test indicate?

Answer 27

necrotic pulp

Question 28

When is test drilling used and how is it done?

Answer 28

Used when full coverage restorations present, other forms of testing impossible

no LA given, cut into tooth dentine. if pain is felt, tooth is vital

Question 29

What is an alternative to drilling?

Answer 29

¡ Isolation crowned tooth with rubber dam
¡ (No LA)
¡ Spray cold water and air
¡ Assess patient response

Question 30

What are the clinical factors that may affect pulp?

Answer 30

¡ Carious pulp exposure
¡ Age
¡ Periodontal disease
¡ Previous pulpal insult/ trauma

Question 31

What changes with age?

Answer 31

¡ Continued dentine formation
¡ Reduced pulp size and volume

¡ Increased:
¡ Fibrous components
¡ Calcification

¡ Decreased:
¡ Cellular components
¡ Number of blood vessels and nerves

¡ Overall:
¡ Pulp less likely to reverse an inflammatory response

Question 32

What happens to pulp in moderate/severe PD?

Answer 32

prematurely aged pulp

less resistant to inflammation than healthy pulp

Question 33

What can previous pulpal insult cause?

Answer 33

¡ Tubule occlusion
¡ Reparative dentine formation
¡ Pulpal fibrosis
¡ “Premature aging” of pulp
¡ Less likely to heal than healthy pulp

Question 34

How can pulp vitality be maintained?

Answer 34

¡ Prevention of pulpal damage
¡ Step-wise excavation
¡ Seal in caries

¡ Vital pulp therapy
¡ Pulp capping
¡ Partial/Cvek pulpotomy
¡ Complete pulpotomy

Question 35

What are examples of MATERIALS FOR VITAL PULP THERAPY?

Answer 35

¡ Zinc phosphate
¡ Zinc oxide eugenol
¡ Calcium hydroxide - e.g. Dycal
¡ Tricalcium phosphate
¡ Resins – e.g. composite
¡ RMGI - e.g. Vitrebond
¡ Bioceramics – e.g. MTA, Biodentine

Question 36

advantages VS disadvantages of calcium hydroxide?

Answer 36

ADVANTAGES
High pH – Stimulates fibroblasts and reparative dentine formation due to irratation, kills acidic bacteria
Easy to use - quick set time
Radiopaque

DISADVANTAGES
Weak (low CS)
Soluble
Does not bond

Question 37

advantages VS disadvantages of MTA?

Answer 37

ADVANTAGES
High pH
Creates bacterial-tight seal
Sets hard enough to act as base for restorative material
Biocompatable

DISADVANTAGES
Prolonged setting time
Discolouration of crown (grey MTA contains iron)

Question 38

What is biodentine?

Answer 38

Similar to MTA, but
¡ Quicker setting
¡ No discolouration

Question 39

What is the process of cvek pulpotomy?

Answer 39

¡ 1-2mm coronal pulp removed initially (with high speed)

¡ Additional pulp removed if bleeding excessive

¡ Once healthy/vital pulp tissue reached – stop

¡ Rinse with 5% NaOCl

¡ Place Ca(OH)2, MTA or Biodentine over pulp tissue

¡ Place sealing restoration (e.g. GI)

¡ Place restoration (e.g. composite)

Question 40

What colour is healthy pulp and how is bleeding controlled in healthy pulp?

Answer 40

light red
with saline

Question 41

What does inflammed tissue look like?

Answer 41

crimson and bleeds a lot

Question 42

What is difference between a partial and a CVEK pulpotomy?

Answer 42

CVEK is 1-2mm removel

partial is additional

Question 43

What is a complete pulpotomy?

Answer 43

Same as previous procedure except entire pulp removed from pulp chamber
Pulp in root canals retained

Question 44

What are treatment options for unexposed pulp?

Answer 44

¡ Indirect pulp cap
¡ Stepwise excavation
¡ Seal caries in

Question 45

What are treatment options for exposed pulp?

Answer 45

Direct pulp cap
Partial coronal pulpal removal – Partial pulpotomy
Complete coronal pulp removal – Complete pulpotomy
Full pulpal removal – Pulpectomy
Progress to full RCT