Care of the pulp Flashcards
1
Q
What cells are found in the pulp
A
odontoblasts
2
Q
What nerves are found in the pulp
A
- alpha fibres (myelinated)
- C fibres (unmyelinated)
3
Q
Are blood vessels found in the pulp?
A
yes
4
Q
how can you tell that the pulp is vital
A
if it responds to stimuli
5
Q
can the pulp regenerate
A
yes
6
Q
what is the relationship with dentine?
A
close relationship, procedures in dentine = treatment of both pulp and dentine
7
Q
what are the functions of the pulp
A
nutrition
sensory
- temp
- pressure
- pain
protective
- tertiary dentine formation (odontoblasts)
- reparative healing
formative
- secondary dentine
8
Q
how can you injure the pulp
A
- caries
- cavity preparation (heat generation, type of bur used)
- restorations (restorative materials/ microleakage/ etch)
- dehydration of dentine (air, water)
- trauma
- cutting odontoblast processes
- toothwear
- periodontal pathology
- orthodontic treatment
- radiation therapy
9
Q
is it better to have more or less remaining dentine thickness
A
more (less damage to pulp)
10
Q
how can the restoration material cause injury to the pulp
A
- toxicity
- water absorption
- heat of reaction
- poor marginal adaption/ seal
- cementation of restoration
11
Q
Why is it that ‘the deeper the cavity, the greater the dentine premeability’?
A
dentine tubules increase in number(? - see structure of tooth tutorial) and diameter as they approach the pulp
12
Q
what things can penetrate the pulp via the dentine tubules
A
bacterial substances polysaccharides antibodies immune complexes complement proteins tissue destruction products
13
Q
what nerve fibres contribute to dental pain
A
Alpha and C
14
Q
What kind of pain do Alpha fibres contribute to
A
sharp pain
15
Q
What kind of pain do C fibres contribute to
A
dull/aching pain
increased pulpal blood flow
increased pulpal pressure
16
Q
Are alpha fibres myelinated or unmyelinated
A
myelinated
17
Q
Are C fibres myelinated or unmyelinated
A
unmyelinated
18
Q
how do you test the alpha fibres are responding (vitality)
A
Electric pulp test (EPT)
19
Q
why is it important to determine/diagnose pulpal health
A
because diagnosis drives treatment plan
20
Q
what are the 2 types of classification of diagnosis
A
pulpal diagnosis
periapical diagnosis
21
Q
What are the different pulpal diagnosis’s
A
Healthy pulp Reversible pulpitis Irreversible pulpitis - symptomatic - asymptomatic Necrotic pulp Previously treated Previously initiated therapy
22
Q
What are the different periapical diagnosies
A
Normal Periapical periodontitis - Symptomatic - Asymptomatic Acute apical abscess Chronic apical abscess Condensing osteitis
23
Q
What indicates a healthy pulp
A
vital
- free of inflammation
24
Q
why might a healthy pulp be removed
A
if endodontic treatment is indicated for:
- elective or prosthetic purposes
- traumatic pulp exposure (ideally treat within 24 hours, but if not RCT required)
25
Describe the pulp in reversible pulpitis
vital but inflamed pulp
can reverse to health if adequate vital pulp therapy performed
26
how can you diagnose reversible pulpitis
regular response to sensitivity tests (many dianostic mistakes made)
27
what characterises reversible pulpitis
- pain to cold, lasts a short time
- hydodynamic expression - microleakage (A fibres)
- no change in pulp blood flow
28
what characterises irreversible pulpitis
- vital pulp
- spontaneous pain, intermittent, sleep disturbance
- negative to cold, pain to hot e.g. tea/ coffee (C fibres)
- increase in pulpal blood flow
29
what characterises necrotic pulp
non-vital pulp
| partial or total necrosis
30
what are the treatment options for necrotic pulp
mature teeth (closed apices):
1. RCT
2. extraction
immature teeth with open apices
1. pulpotomy
2. pulpectomy then full RCT
3. extraction
31
what are the treatment options for irreversible pulpitis
(investigations suggest pulpal inflammation can not heal)
treatment options:
1. pulpectomy required then RCT
2. extraction (unrestorable tooth, patient preference)
32
What characterises normal periapical tissues
Not sensitive to percussion or palpation
Radiographically:
1. lamina dura intact
2. PDL space uniform
33
What characterises symptomatic periapical periodontitis
inflammation of the apical periodontium
Pain:
- biting
- percussion and/or
- palpation
May have periapical radiolucency
Severe pain to percussion and/or palpation highly indicative of degenerating pulp
-RCT required
34
What characterises asymptomatic periapical periodontitis
Inflammation and destruction of the apical periodontium (of pulpal origin)
appears as an apical radiolucency
no present clinical symptoms
- no pain on percussion
- no pain on palpation
35
What characterises an acute apical abscess
- inflammatory reaction to pulpal infection and necrosis
- rapid onset
- spontaneous pain
- extreme tenderness to pressure
- pus formation
- swelling
- may be no radiographic signs of destruction
- malaise
- fever
- lymphadenopathy
36
What characterises a chronic apical abscess
- inflammatory reaction to pulpal infection and necrosis
- gradual onset
- little or no discomfort
- intermittent discharge of pus through sinus tract
- peripapical/periradicular radiolucency
can be identified by:
- carefully placing GP cone into sinus tract
- take radiograph
37
What characterises condensing osteitisis
diffuse radiopaque lesion
- represents localised bony reaction to a low-grade inflammatory stimulus
- usually seen at apex of tooth
38
what are signs of a non-vital tooth
Discolouration
- yellow
- grey
- pink
sinus
gross caries
large restoration
radiographic evidence
- periapical radiolucency
- periradicular radiolucency
39
What causes a tooth to turn yellow
obliteration of dentine tubules
40
What causes a tooth to turn grey
blood products in dentine tubules
41
What causes a tooth to turn pink
cervical resorption
42
What is the primary function of a sensibility test
to differentiate "vital" from "non-vital"
43
how do you get around the fact that sensibility tests are very subjective
compare the patient's response with a contralateral tooth then re-examine same tooth
44
What are the different sensibility tests
1. Electric pulp tests (EPTs)
2. Thermal tests
- cold tests
- heat tests
3. Test drilling
45
What substance is used in the cold sensibility tests
- frozen sticks of CO2 or ice
- cotten pellet/ roll sprayed with
ethyl chloride, difluorodichloromethane or endo-ice
46
What substance is used in the hot sensibility tests
hot gutta percha (GP)
47
What are the problems with sensibility tests
- these tests stimulate nerve fibres (don't assume that nerve fibres in pulp correlates to vital blood supply)
- these tests do not indicate state of blood supply
- tooth vitality is related to blood supply, not nerve stimulation (laser doppler needed to assess blood flow)
48
What fibres are stimulated using an EPT
A delta fibres (?)
unmyelinated C fibres may or may not respond
49
What is the procedure for the EPT
Teeth thoroughly dried
- Prevents current transfer to adjacent teeth
Isolate tooth/teeth
```
Conducting medium (toothpaste/ fluoride gel) required
- Tip of EPT probe
```
EPT probe placed on incisal edge or cusp tip adjacent to pulp horn
- Most sensory nerves found here
Patient completes circuit by holding handle of EPT
Current slowly increased
- Occurs automatically
- Pt. indicates when a tingling/ heat sensation is felt (Can pull probe away from tooth)
50
What does a positive response from the EPT indicate
1. Vital pulp tissue in coronal aspect of pulp chamber
2. No indication of reversibility of inflammation (healing)
3. No correlation between pain threshold and pulp condition (measurement of electric voltage/ score is not accurate)
51
What does a negative response from the EPT indicate
1. Reliable indicator for pulpectomy procedure in 97.7% cases
2. EPT of young pulps (teeth with open apices) or recently traumatised teeth
(unreliable)
52
How does thermal testing work
believed to work by hydrodynamic forces
- fluid movement in dentinal tubules (due to thermal stimulus)
- activates pulp's sensory nerve receptor units in pulp
53
What is a negative response to cold test indicate
highly indicative of pulpal necrosis
54
what is the procedure for cold test
teeth carefully dried and isolated
place cole object close to pulp horn
either frozen stick or cotton pellet/ roll sprayed with e.g. ethyl chloride
55
Why do you have to be super cautious with heat tests
too much heat may cause irreversible pulpitis
56
what pain happens with heat tests
Initial stimulation of A-delta fibres
(Sharp pain)
Continued stimulation results in C-fibre activation
(Dull radiating pain)
57
What is the procedure for heat tests
Vaseline on tooth
| Apply hot gutta percha/ green stick to tooth
58
what is a negative heat test indicative of
necrotic pulp
| Not possible to ascertain degrees of reversibility of inflamed symptomatic pulp
59
When is test drilling used
Used when full coverage restorations present
60
what is the procedure for test drilling
No local anaesthetic given
Cut into tooth
61
what does a negative response to test drilling indicate
- Patient reports severe pain or no pain felt when cutting dentine
- Sensitivity-like response to dentine preparation – tooth is vital
62
What is an alternative to test drilling
Isolation crowned tooth with rubber dam
(No LA)
Spray cold water and air
Assess patient response
63
what are the different clinical factors which affect tooth vitality
- carious pulp exposure
- age
- periodontal disease
- previous pulpal insult/ trauma
64
how does carious pulp exposure impact treatment
Pulp exposed to caries and bacteria
Vital treatment of carious exposures less than 50% successful
Therefore RCT required
However – not in all cases
• E.g. Immature teeth with incomplete root development – Consider removal of necrotic parts of pulp only (Pulpotomy)
65
How does increasing age affect the pulp
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
66
How does periodontal disease affect the pulp
Moderate to severe periodontal disease
Result: “prematurely aged” pulp
Pulp in periodontally involved tooth
less resistant to inflammation than healthy pulp (not universally accepted)
67
how does a previous pulp insult affect pulp
Caries, caries removal and restorative procedures
- Tubule occlusion (Reparative dentine formation,
Pulpal fibrosis)
“Premature aging” of pulp
(Less likely to heal than healthy pulp)
68
how do you maintain pulp vitality
prevention of pulpal damage
| treatment of pulpal damage
69
How can you prevent pulpal damage
Know tooth anatomy
- Size, location and proximity of pulp
- Pre-assessment (Radiographs)
Avoid drilling into pulp
- Stop if close to pulp
- Caries can be left over pulpal floor in some cases
(Placement of well-sealed restoration)
Cavity close to pulp
- Use of cavity sealers
- Indirect pulp cap
Cavity into pulp (exposure)
- Direct pulp cap
70
How can cavity sealers help prevent pulpal damage
Protect pulp from:
- bacteria and their products
- toxic effects during setting phase of restorative material
Whole exposed pulpal dentine must be covered
Material must:
- adhere to dentine rather than restorative material
be thin
(Otherwise – reduces strength of restorative material)
- Not dissolve in biological liquids
```
Types
- Varnishes
(Material dissolved in organic solvent e.g. ether)
- Liners
- Base materials
```
71
How can a cavity base/liner help prevent pulpal damage
Thicker sealant
- Thermal protection
(Thermal effects arising through restorative material)
Examples:
- Zinc phosphate
- Zinc oxide eugenol
- Calcium hydroxide
e. g. Dycal
- Resin modified glass ionomers (RMGI)
e. g. Vitrebond
72
What are the advantages and disadvantages of calcium hydroxide
Advantages
Bacteriocidal/ bacteriostatic
- High pH – Stimulates fibroblasts
(Reparative dentine formation (healing))
- Stimulates recalcification of demineralised dentine
(by stimulating pulpal cells)
- Neutralises low pH from acidic restorative materials
```
BUT:
- Cytotoxic
(Can kill pulp cells)
- Weak cement
- Very soluble if not protected
```
73
How do dentine bonding agents help protect the pulp
Dentine primers with/ without adhesives are both tolerated by the pulp
Marked reduction in microleakage demonstrated by dentine bonding agents
However
Use is VERY “technique sensitive"
74
What is a summary of treatment options for pulpal damage
Which liner and when?
Dependent upon the RDT
Treatment of pulpal damage
Indirect pulp cap
Or stepwise excavation or seal caries in
Direct pulp cap
Partial pulpal removal – Pulpotomy
Full pulpal removal – Pulpectomy
Progress to RCT
