Care of the pulp Flashcards
What is the pulp?
- Tissue that lies in the middle of the tooth
Is the pulp a vital tissue?
- Yes because it has a blood supply
What cells are present in the pulp?
- Odontoblasts
What nerves are present in the pulp? (2)
- Alpha fibres (myelinated)
- C-fibres (unmyelinated)
What characteristics does pulp have since it is a vital tissue? (2)
- Responds to stimuli
- Has regenerative potential
What is the nerve plexus of Raschkow?
- Sensory nerve fibres that originate from superior and inferior alveolar nerves innervate the odontoblast layer of the pulp cavity
- These nerves enter the tooth through the apical foramen as myelinated nerve bundles
- They branch to form subodontoblastic nerve plexus of Raschkow
What are the functions of the pulp? (4)
- Nutrition
- Sensory
- Protective
- Formative
What are the sensory functions of the pulp? (3)
Can sense:
- Temperature
- Pressure
- Pain
What is the protective function of the pulp?
- Tertiary dentine formation (odontoblasts) - reparative healing
What is the formative function of the pulp?
- Secondary dentine
What is the correlation between clinical symptomatology and pulpal histopathology?
- Poor correlation between what’s going on histopathologically and what the patient is feeling (symptoms)
What different things do we need to know the pulps reaction to? (4)
- Caries
- Operative manipulations
- Trauma
- Periodontal disease
Etc.
What are things that can cause injuries to the pulp? (14)
- Caries
- Cavity preparation
- Restorations (materials: microleakage, etch)
- Trauma
- Tooth wear
- Periodontal pathology
- Orthodontic treatment (forces applied to the tooth)
- Radiation therapy
- Cavity/crown preparation (heat generation, type of bur)
- Dehydration of dentine (air, water)
- Cutting odontoblast processes
- Direct injury to the pulp
- Remaining dentine thickness
- Restoration material
For what reasons can the type of restoration material cause damage to the pulp? (5)
- Toxicity
- Water absorption
- Heat of reaction
- Poor marginal adaptation/seal
- Cementation of restoration
What do dentinal tubules do as they approach the pulp?
- They increase in diameter
Therefore: the deeper the cavity, the greater the dentine permeability - Dentine tubules DO NOT increase in number as they approach the pulp
What is dentine permeable to? (6)
- Bacterial substances
- Polysaccharides
- Antibodies
- Immune complexes
- Complement proteins
- Tissue destruction products
What is key towards initiating and maintaining pulpal and periradicular pathology?
- Micro-organisms
Pain will typically fall into 2 categories. What are the 2 categories and what type of fibre stimulates them?
- Sharp pain = alpha
- Dull/aching pain = C fibres
What are the characteristics of alpha fibres? (3)
- Myelinated
- Sharp pain
- Stimulated by electric pulp testing
What are the characteristics of C fibres? (4)
- Non-myelinated
On stimulation:
- Dull/aching pain
- Increased pulpal blood flow
- Increased pulpal pressure
Why is there increased pulpal pressure when c fibres are stimlated?
- When C fibres are stimulated you get increased blood flow into the tooth which increases the pressure in the tooth - as it has no where to expand
What are the different possible pulpal diagnoses? (6)
- Healthy pulp
- Reversible pulpitis
- Irreversible pulpitis (symptomatic/asymptomatic)
- Necrotic pulp
- Previously treated
- Previously initiated therapy
What is the pulpal diagnosis ‘previously treated’?
- A clinical diagnostic category indicating that the tooth has been endodontically treated and the canals are obturated with various filling materials, other than intracanal medicaments
What is the pulpal diagnosis ‘previously initiated therapy’?
- A clinical diagnostic category indicating that the tooth has been previously treated by partial endodontic therapy e.g. pulpotomy/pulpectomy
What is the pulpal diagnosis ‘healthy pulp’?
- Vital: free of inflammation
- symptom free and normally responsive to vitality testing
In what cases would healthy pulp be removed?
Removed if endodontic treatment indicated for:
- Elective or prosthetic purposes
- Traumatic pulp exposure: ideally treat exposure within 24 hours but if not RCT is required
- In very severe wear cases: as a result of this the pulp has managed to place lots of tertiary dentine - pulp is vital but need to get rid of it so you can place a crown
What is the pulpal diagnosis ‘reversible pulpitis’?
- Vital
- Inflamed pulp
- Investigations suggest it can reverse to health if adequate vital pulp therapy performed
- Many diagnostic mistakes made
- Regular response to sensibility tests
What kind of response do you get from sensibility tests with reversible pulpitis?
- Regular response to sensibility tests
What is the pulpal diagnosis ‘irreversible pulpitis’ (symptomatic or asymptomatic)?
- Vital
- Inflamed
- Investigations suggest pulpal inflammation can not heal
- Symptomatic = patient in pain
- Asymptomatic = no pain felt by patient
What are the treatment options for irreversible pulpitis? (2)
- Pulpectomy required then RCT
- Extraction (unrestorable tooth or patient preference)
What does the difference between reversible and irreversible pulpitis depend on?
- Difference depends on clinical symptoms seen
What is occurring in reversible pulpitis? (3)
- Pain to cold, lasts a short time
- Hydrodynamic expression - microleakage (A-fibres)
- No change in pulp blood flow
What is occurring in irreversible pulpitis? (3)
- Spontaneous pain, intermittent, sleep disturbance
- Negative to cold, pain to hot (C-fibres)
- Increase in pulpal blood flow
What is the pulpal diagnosis ‘necrotic pulp’?
- Non-vital pulp
- Partial or total necrosis
What are the treatment options for necrotic pulp in mature teeth (closed apices)? (2)
- Root canal treatment
2. Extraction
What are the treatment options for necrotic pulp in immature teeth (with open apices)? (3)
- Pulpotomy
- Pulpectomy then full RCT
- Extraction
What is a pulpotomy?
- Remove some of the pulp (the necrotic pulp) then seal over the vital pulp
What is a pulpectomy?
- Removal of the entire structure of a tooth, including the pulp tissue in the roots
What is the periapical diagnosis ‘normal periapical tissues’?
- Not sensitive to percussion or palpation
- Radiographically: lamina dura intact, PDL space uniform
Radiographically what does it look like if periapical tissues are normal? (2)
- Lamina dura intact
- PDL space uniform
What does it look like radiographically if there is damage to the lamina dura?
- If start to see a blurring effect where you can’t clearly see the outline of a tooth on a radiograph then the lamina dura is damaged
What is the periapical diagnosis ‘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