AGD Endodontic Diagnosis and Treatment 3 — Questions and Answers
Question 1: A patient reports lingering pain to cold stimulation lasting more than 30 seconds in an otherwise intact tooth. What is the most appropriate treatment?
- Monitoring and fluoride application
- Desensitizing toothpaste prescription
- Root canal treatment (Correct answer)
- Tooth extraction
Correct answer: Root canal treatment
Lingering pain to cold lasting >30 seconds is a classic sign of irreversible pulpitis, which requires endodontic treatment to resolve.
Question 2: EDTA (ethylenediaminetetraacetic acid) is used in endodontics primarily to:
- Kill bacteria in the canal system
- Remove the smear layer by chelating calcium (Correct answer)
- Dissolve necrotic pulp tissue
- Lubricate rotary instruments only
Correct answer: Remove the smear layer by chelating calcium
EDTA is a chelating agent that removes the inorganic smear layer from dentinal walls, improving sealer penetration into dentinal tubules.
Question 3: Which of the following is a contraindication to single-visit root canal treatment?
- Vital pulp with irreversible pulpitis
- Acute apical abscess with systemic involvement (Correct answer)
- Normal healthy patient with a calcified canal
- Retreatment of a previously obturated tooth
Correct answer: Acute apical abscess with systemic involvement
Acute apical abscess with systemic signs (fever, lymphadenopathy) is a contraindication to completing single-visit RCT, often requiring drainage and antibiotics first.
Question 4: The 'S-shaped' root canal curvature most commonly seen in which tooth?
- Maxillary central incisor
- Mandibular second premolar (Correct answer)
- Maxillary second molar
- Mandibular second molar
Correct answer: Mandibular second premolar
The mandibular second premolar frequently has a dilacerated or S-shaped root, making canal navigation and instrumentation challenging.
Question 5: During retreatment, which solvent is most commonly used to soften gutta-percha for removal?
- Sodium hypochlorite
- Chloroform or eucalyptol (Correct answer)
- EDTA
- Hydrogen peroxide
Correct answer: Chloroform or eucalyptol
Chloroform or eucalyptol softens gutta-percha to facilitate its removal during endodontic retreatment.
Question 6: A 'phoenix abscess' refers to which clinical scenario?
- An abscess developing on a previously asymptomatic necrotic tooth (Correct answer)
- An abscess formed after trauma to a vital tooth
- A periapical cyst that becomes infected
- Acute suppurative periodontitis of a vital tooth
Correct answer: An abscess developing on a previously asymptomatic necrotic tooth
A phoenix abscess is an acute exacerbation occurring in a tooth with chronic apical periodontitis or a pre-existing periapical lesion, often triggered by instrumentation.
Question 7: Which rotary file system design feature most reduces the risk of canal transportation in curved canals?
- Larger taper with rigid cross-section
- Non-cutting safety tip with flexible NiTi alloy (Correct answer)
- Aggressive rake angle and sharp cutting edge
- Stainless steel composition for strength
Correct answer: Non-cutting safety tip with flexible NiTi alloy
Non-cutting safety tips prevent apical ledging while flexible NiTi alloy allows files to follow canal curvature, reducing transportation risk.
AGD Endodontic Diagnosis and Treatment 3
A patient reports lingering pain to cold stimulation lasting more than 30 seconds in an otherwise intact tooth.
What is the most appropriate treatment?