Endodontics Theory Flashcards
What is endodontics?
The study of the dental pulp and the tissues surrounding the root (periradicular tissues)
What is Stage 1 of a RCT?
Removal of vital or necrotic pulp tissues from the pulp chamber and root canal by shaping and cleaning
What is stage 2 of a RCT?
Sealing the pulp chamber and canals at both apical and coronal levels
What three things make up the endodontic triad?
Mechanical Shaping, Chemical Cleaning, Obturation to seal
What can you diagnose at the coronal part of the tooth from traditional x-rays?
the size, quality and removability of restorations; any caries and the restorability of the tooth; the space between the roof and the floor of the pulp chamber
What can you diagnose about the apical area of the tooth from traditional x-rays?
the length of root; the curvature of the roots; any radiolucencies; any periodontal defects; number of roots and canals; condition of lamina dura; PDL shade and width; any root resorption; any canal calcification; any root fractures
What type of advanced imaging can you use for endodontics?
CBCT or Micro CT
What can using CBCT or Micro CT imaging allow you to do?
accurately plan your treatment in advance
What are the examination procedures needed to make an endodontic diagnosis?
medical and dental history; chief complaint; clinical exam; clinical testing; radiographs; special tests
What is the clinical classification of normal pulp?
pulp is symptom-free and normally responsive to pulp testing
What is Reversible Pulpitis?
Inflammation of the pulp causing discomfort when exposed to a stimulus. The discomfort should resolve within a few seconds of the stimulus being removed
What are some typical etiologies of Reversible Pulpitis?
dentine hypersensitivity; deep caries/restorations
What is are Symptoms of Irreversible Pulpitits?
Pain on a stimulus that lingers. Can also cause spontaneous or referred pain.
What are some typical etiologies of irreversible pulpitis?
deep caries, extensive restorations, fractures exposing the pulpal tissues
What is asymptomatic irreversible pulpitis?
the vital inflammed pulp is incapable of healing and there are no clinical symptoms
What is pulp necrosis?
death of the dental pulp
What are some symptoms of pulp necrosis?
the pulp is non-responsive to pulp testing and is asymptomatic
Does pulp necrosis cause apical periodontitis?
no unless the canal itself is infected
What does ‘previously treated’ mean in regards to clinical diagnosis?
the tooth has been endodontically treated and canals are obturated with filling materials other than medicines
What does ‘previously initiated therapy’ mean in regards to clinical diagnosis?
the tooth has been previously treated by partial endodontic therapy such as pulpotomy or pulpectomy
What is symptomatic apical periodontitis?
inflammation of the apical periodontium
What is another phrase for symptomatic apical periodontitis?
Acute Apical Periodontitis (AAP)
What are some symptoms associated with Acute apical periodontitis?
pain on biting and/or percussion or palpation, radiographic changes
What is asymptomatic apical periodontitis?
inflammation and destruction of the apical periodontium that is of pulpal origin
What is another phrase for asymptomatic apical periodontitis?
chronic apical periodontitis (CAP)
What are some symptoms associated with Chronic Apical Periodontitis?
Apical radiolucency, no clinical symptoms
What is a chronic apical abscess?
an inflammatory reaction to pulpal infection and necrosis
What are some symptoms of a chronic apical abscess?
intermittent discharge of pus through a sinus tract, little or no discomfort, radiolucency around the apex
What is an Acute apical abscess?
inflammatory reaction to pulpal infection and necrosis
What are some symptoms of an acute apical abscess?
spontaneous pain, extreme tenderness upon pressure, pus, swelling of surrounding tissues, fever, feeling unwell, no radiolucency
What is condensing osteitis?
localised bony reaction to a low-grade inflammatory stimulus
What are some symptoms of condensing osteitis?
potential pain, diffuse radiopaque lesion normally at the apex of the tooth
What are some examples of treatments for vital pulp?
pulpotomy, pulpectomy, pulp extirpation, indirect pulp capping, stepwise caries removal, direct pulp capping, chemo-mechanical caries removal method
What is a pulpotomy?
amputates the inflamed coronal pulp and preserves the vitality of the pulp in the roots
What is a pulpectomy?
complete removal of pulp from crown and roots
What is pulp extirpation?
complete removal of dental pulp using a cleaning and shaping technique
When would indirect pulp capping be performed?
When the cavity preparation is in close proximity to the pulp but with no obvious exposure
What is indirect pulp capping?
a liner such as calcium hydroxide is placed over a layer of deep carious dentine which is firm but discoloured before it is covered by a provisional restoration
What is direct pulp capping?
treatment of exposed pulp by sealing the pulpal wound with a dental material such as calcium hydroxide/MTA/biodentine to facilitate formation of reparative dentine
What is an access cavity?
an endodontic coronal preparation which enables unobstructed access to the coronal orifices
What are you aiming to achieve with an access cavity?
straight line access to the apical foramen, complete deroofing of the pulp chamber, conserving sound tooth structure, be able to provide support to temp fillings
What is important to remember before starting an access cavity and why?
You should remove all the existing restorations to expose the naked tooth to assess the restorability of the tooth
When do you not need to remove previous restorations?
if it is a recently fitted crown with a good outcome
A study of what is needed before starting an access cavity prep?
pre-op periapical radiographs
Why is it important to assess pre-op radiographs prior to access cavity prep?
assess tooth morph, anatomy of root canal system, length of canal, position and size of pulp chamber, distance of pulp chamber from occlusal surface, position of apical foramen, if there is any calcification/resorption of the roots
What can happen if you don’t completely remove the roof off the pulp chamber?
there could be contamination or infection of the endodontic space, or discolouration of the endontically treated teeth
Why is it important for the access cavity to permit the removal of all the chamber contents?
good endodontic cleaning begins with the removal of the endodontic contents from the pulp chamber and its horns
Why is it important for the access cavity to permit complete and direct vision of the floor of the pulp chamber?
the landmarks on the floor help to identify the canal openings
Why is it important that endodontic instruments should not be deflected by any obstruction in the crown?
the instruments should never touch the walls of the pulp chamber and should be able to move freely in the canal, they must be able to work on all sides of the canal, obstructions in the crown might fracture the instrument
How can you check the position and depth of the pulp chamber?
you can align the burr and handpiece against the radiograph
Are round or tapered burrs better for penetrating into the pulp chamber?
tapered
How can you remove dentinal overhangs from the pulp chamber?
moving the burr in and out of the pulp chamber in without touching the floor of the pulp chamber
Is the access cavity preparation larger in older or younger patients?
younger
What shape should you aim to achieve with your access in anterior teeth?
triangular
What shape should you aim to achieve with your access in premolars?
oval buccally-lingually
What shape should you aim to achieve with your access in premolars?
trapezoidal or triangular
What is periapical periodontitis?
inflammation of the periodontal ligament around the apex of the tooth
What is the most common cause of periapical periodontitis?
infection from caries that reaches the pulp causing pulpitis and pulp necrosis
What are three potential causes of periapical periodontitis?
infection, trauma to the apical region, chemical
What are three ways trauma can occur to the apical region leading to periapical periodontitis?
high fillings, RCT, excessive occlusal force
What are two ways chemicals may cause periapical periodontitis?
root filling materials extruding over the apex, irritant antiseptics
Why may high fillings cause trauma to the periapical tissues resulting in periapical periodontitis?
the patient will bite here first and most of the biting force will be applied through one area
What are the two ways we can classify periapical periodontitis?
acute and chronic
What are some clinical features of acute periapical periodontitis? (name 4)
no hot/cold symptoms, TTT, tooth extruded from socket due to swelling, visible swelling, lymph node involvement, fever, generally feeling unwell
What might you see radiographically for acute periapical periodontitis?
widening of the PDL
What microscopic features might you see for acute periapical periodontitis?
acute inflammation between the apex and bone, pus, neutrophils, swelling in pdl, increased blood flow
What cells replace the apical pdl in chronic periapical periodontitis?
chronic inflammatory cells such as lymphocytes, epithelial cells
What are some clinical features of chronic periapical periodontitis?
symptomless, mild pain, localised tenderness, discoloured tooth, sinus
What microscopic features might you see for chronic periapical periodontitis?
lymphocytes and plasma cells, resorption of bone, epithelial proliferation
What are cell rests of malassez?
epithelial cell rests left over from tooth formation
What are four ways you can manage chronic periapical periodontitis?
open drainage, RCT, removal of tooth apex, extraction
What are the four ways acute periapical periodontitis can progress?
resolution, drainage into the oral cavity via PDL space, sinus formation, hypercementosis
What determines the level of complications that may develop as a result of periapical periodontitis?
the severity, duration of irritant, integrity of patients defence mechanisms
into which tissues can the infection due to periapical periodontitis spread?
skin, bone, lymph node, blood stream
What is ludwigs angina?
infection that has spread to the floor of the mouth and crosses the midline which can cause airway obstruction
How can you classify epithelial cysts?
odontogenic cysts or non-odontogenic cysts
Are developmental or inflammatory odontogenic cysts the classic ‘dental cyst’?
inflammatory
How can you classify cysts of the jaws?
epithelial cysts and non-epithelialised primary bone cysts
How can inflammatory odontogenic cysts develop?
pre-existing chronic periapical periodontitis or loss of tooth vitality
