Revision lecture Flashcards
Why do we do endodontology?
- Remove pain
- Restore health of the pulp chamber and root canal system
- Restore health of peri-radicular regions
- Enable tooth to be restored
- Bring tooth into function
What is the success rate of an RCT?
85-95%
What is the success rate of a reRCT?
77-80%
What needs to be considered when assessing if a tooth can be restored?
-Amount of sound tooth tissue remaining in crown and root
- Periodontal condition
-Occlusal consideration
What are the indications for root canal treatment?
Teeth that are functionally and aesthetically sound, and have a reasonable prognosis
- Irreversibly damaged/necrotic pulp (w/wo apical periodontitis)
- Elective devitalisation
(post space for misaligned teeth/dubious pulp prognosis prior to tooth prep)
What are the contraindications for root canal treatment?
- Teeth that cannot be made functional or restored with limited ferrule effect
- Teeth with insufficient periodontal support
- Teeth with poor prognosis such as extensive internal or external resorpsion/extensive vertical fractures
- Pt unable to tolerate rubber dam/uncooperative
- Complex anatomy
- Poor oral condition that cannot be improved within a reasonable time
Name some special investigations required when considering an endodontic diagnosis
Medical/dental history, presenting complaint, clinical exam
Radiographic imaging
Clinical photographs
Sensibility testing
Periapical tests (TTP, TTpalp, tooth slooth)
6PPC
Study casts
Interocclusal ICP/RCP record
Facebow record
Diet record
Parafunctional habits
Salivary function
Disclosing plaque
Transillumination
Selective anesthesia
Test cavity
Can we calculate a WL from a panoramic radiograph?
No, as there is x1.2 mag on a panoramic so a PA is needed.
5% more magnification on panoramic
Superimposition/geometric distortion/lack of standardisation or reproducability
Can periapical lesions confined within cancellous bone always be detected by periapical radiography?
Not always, depends on the thickness of cortex bone
Why are root canal filled teeth weaker?
- Loss of tooth structure
- Altered physical properties
- Loss of proprioception
Why cuspal coverage is recommended- 38% more successful
What are the requirements of posts?
Minimum length of 4-5mm of gutta percha
No space between post and GP
Post length = to the length of crown of 2/3 root length
Retention
Does not strengthen tooth
What are the symptoms of reversible pulpitis?
Pain does not linger after stimulus is removed
Pain is difficult to localise (pulp contains nociceptive fibres not proprioceptor fibres)
Tooth not TTP
Why might reversible pulpitis occur?
Dental caries
Erosion
Attrition
Abrasion
Trauma
Operative procedures eg RSD
How can reversible pulpitis and dentinal hypersensitivity be distinguished?
Generalised gingival recession? Check sensitivity to 3 in 1 air
What is the treatment of reversible pulpitis?
- Cover exposed dentinal tubules
- Remove the stimulus (& restore tooth)
What are the symptoms of irreversible pulpitis?
Pain can develop spontaneously
Severe pain
Pain lingers after stimulus is removed (30s or more)
Response lasts from minutes to hours
Pain to hot liquids relieved by cold
Over the counter analgesics typically ineffective
If a dental pain is localised, what does it show?
PDL is involved
What is the treatment for irreversible pulpitis?
RCT or XLA
What is hyperplastic pulp? What is the tx?
Form of irreversible pulpitis known as a pulp polyp
Due to proliferation of chronically inflamed pulp tissue
Tx- RCT or XLA
Why may some teeth be nonresponsive to sensibility testing?
- Calcification
- Recent history of trauma
- Simply, the tooth isn’t responding
- Pulp necrosis
Hence sensibility testing must be of a comparative nature
What is the tx of necrotic pulp?
RCT or XLA
How many signs & symptoms are required for a RCT to be carried out?
2
What do you do if you observe pulp calcification of a tooth?
No symptoms? -> review and monito
Symptoms? -> 2 signs and symptoms- refer to endodontologist
What different kinds of tertiary dentine are laid down in response to environmental stimuli?
Reactionary dentine response to mild stimuli
Reparative dentine in response to strong noxious stimuli
The reactionary dentine is secreted by original odontoblasts, while the reparative dentine is formed by odontoblast-like cells.
What is internal resorption?
Pulp inflammation resulting in the resorption of dentine by dentinoclast cells
What is seen clinically with internal resorption? and Radiographically?
Pink spot
Punched out lesion continuous with the rest of the pulp cavity
What is the tx for internal resorption?
RCT, if resorption is too advanced then XLA
What is chronic apical periodontitis also called?
Periapical granuloma
What is a peri-apical true cyst?
Distinct pathological cavity completely enclosed in an epithelial lining so no communication to the root canal exists
RCT will not fix this, has to be surgically enucleated
What is a peri-apical pocket cyst?
Apical inflammatory cyst sac-like epithelial lined cavity that is open and continuous with the root canal
RCT removes this
What can acute apical periodontitis be caused by?
- Traumatic occlusion
- Bacteria/toxins from infected/necrotic pulps
- Over instrumentation
- Extrusion of irrigants or materials during RCT
Radiographic signs of acute apical periodontitis?
None/PDL widening
Tx of of acute apical periodontitis?
RCT
XLA
What causes chronic apical periodontitis?
Pulp necrosis
What kind of things can be in the HPC when considering chronic apical periodontitis?
Prev pain
Recent restorations in the tooth
RCT been carried out
What will chronic apical periodontitis look like radiographically?
Widening of PDL to apical radiolucency
What is the tx of chronic apical periodontitis?
RCT
XLA
what is condensing osteitis?
Variant of chronic apical periodontitis
Response of trabecular bone to irritation, concentric radiopaque around root
What is the tx for condensing osteitis?
RCT only if symptoms and pulpal diagnosis indicate
What are the different types of perio-endo lesions?
If perio is involved prognosis depends on periodontal treatment and patient response
Name some symptoms of cracked tooth syndrome when considering a vital tooth
Sharp pain on biting or release, occasional pain from cold
Difficult to localise
More common in 2nd molars
What investigations can you do for cracked tooth syndrome?
Tooth slooth
Staining
Transillumination
What tx is there for cracked tooth syndrome for a vital tooth?
Ortho band
Cu band
Temp crown
Cuspal coverage restoration
Name some symptoms of cracked tooth syndrome when considering a non-vital tooth
Dull ache on biting
TTP
Narrow perio pocket adjacent to fracture
Radiographic halo, J shaped diffuse lesion surrounding the root
What other conditions can mimic acute odontogenic pain?
Bruxism
Myofacial pain
Trigeminal neuralgia
Atypical odontalgia
Migrane
Cluster headache
Sinusitis
herpes zoster
REFER IF NO OBVIOUS SIGNS & SYMPTOMS
What is the biological aim of root canal preparation?
Pulpal tissue, bacteria and related irritants from the root canal system are eliminated
What are the mechanical aims of root canal preparation?
- Continuously tapered preparation produced
- Original anatomy is maintained
- The foramen position is maintained
Apical foramen is kept as small as possible
What are the purposes of a rubber dam?
- Prevents inhalation or ingestion
- Prevents infection by saliva
- Enhances access and retracts soft tissues
- Better comfort for pt
- Medico-legal requirement
What is vertucci’s classification?
Complexity of root canals
What size file do you take the WL radiograph with?
15mm
What type of obturation methods are there
Cold lateral condensation
How many mm below the CEJ do we sear off the cones?
3mm below CEJ
How do we ensure safe and effective irrigation?
- Use side venting needle
- Never bind irrigation needle in canal
- Never use excessive force to ‘inject’ solution
- Irrigate slowly
- High volume suction with surgical tip until the solution is clear in the access cavity
- Total of 2-3ml irrigation is advisable at the 1st stage of root canal treatment
What do irrigants do?
Kill micro organisms
Flush out debris from root canals
Dissolve soft tissue (incl necrotic tissue)
Dissolve hard tissues (icl nectrotic tissue and smear layer)
Lubricate instruments
Name some irrigants
Sodium hypochlorite (2.5%)
Chlorhexidine
EDTA
What are the symptoms of a sodium hypochlorite incidient?
Severe pain
Swelling of tissues
Extreme blanching of tissues
Bloody exudate from tooth
Numbness of weakness of facial nerve
What is the management of a sodium hypochlorite incidient?
Irrigate with sterile water
Reassure patient
Analgesics
Immediate referral to A&E/Max fax/ steroids
Purposes of patency filing?
Prevents blockage
Check whether exudate present
Helps maintain & follow anatomy
Helps deliver irrigant apically
What’s a contraindication to use an apex locator?
Pt’s with cardiac pacemakers
What can make a short circuit when using an apex locator?
Canal too moist
Touching metal restoration
Is there a perforation?
Large lateral canal?
What conditions are necessary prior to insertion of a root canal filling?
- Canal must be dry or capable of being dried
- Canal preparation must be complete
- Tooth should be symptom free
- Soft tissues related to the tooth should not show signs of infection eg sinus tract gone
Name some root canal sealers
ZOE sealers
COH sealers
Resin sealers
Glass ionomer sealers
