Endodontics SBA Flashcards
A 28 year old man attends with a continuous aching upper left first permanent molar. It occurs spontaneously, disturbs sleep and is partly relleved by paracetamol. Chewing or biting does not exacerbate the symptoms. The heavily restored UL6 was hyperresponsive to refrigerant (Endofrost°): All other special investigations were normal. Which is the single most likely diagnosis?
A - Acute apical abscess a
B - Atypical facial pain
C - Chronic apical periodontitis
D - Irreversible pulpitis
E - Periodontal abscess
D - irreversible pulpitis
Keywords: spontaneous, wakes at night, not exacerbated by biting
A 45-year-old man has sharp pain to cold from his upper right posterior teeth; the pain ceases immediately on removal of the stimulus. He has multiple cervical abrasion cavities. Which single type of sensory nerve fibre is primarily responsible for his pain? *
A - A-B
B - A-a
С - С
D - Parasympathetic
E - Sympathetic
B - A-alpha
responsible for mediating sharp shooting pains associated with dentine hypersensitivity.
keywords: sharp, ceases immediately
A 29-year old woman is about to have primary RCT on her lower first permanent. premolar At which single stage of root canal preparation would it be most appropriate to use Gates Gliden? *
A- Access
B - Apical preparation
C - Canal identification
D - Coronal flaring
E - Working length determination
D - coronal flaring
A 45 year old man is having RCT on his upper left first premolar. After scouting the canal with a small handfile a rotary file system is introduced with an ISO 25 tip size and a 10-degree taper (25/10) until resistance is felt. Subsequently, files with a smaller taper are introduced until the working length is reached (25/06 - 25/04). What single concept of endodontic preparation does this tech-
nique follow? #
A - Apico-coronal
B - Circumferential
C - Crown-down
D - Modified double flare
E - Step back
C - crown down
A 52 year old woman has a sudden severe onset of severe pain and an altered sensation under her eye, following irrigation during root canal retreatment on a maxillary canine. Which is the single most likely complication?
A - Extrusion of sodium hypochlorite
B - Inadvertent instrumentation of the infraorbital nerve
C - Lateral perforation
D - Root fracture
E - Transportation of apical constriction
A - extrusion of sodium hypochlorite
Keywords: severe pain, altered sensation
A 32 year old man has recently completed RCT on a lower molar that is missing both marginal ridges. Which is the single most appropriate method to restore his tooth?
A - A bonded intracoronal amalgam restoration
B - A bonded intracoronal composite restoration
C - A ceramic inlay
D - A full coverage gold crown
E - A gold inlay
D - full coverage gold crown
Keywords: missing both marginal ridges
A consultant is discussing the aetiology and management of dental caries. On his slides, he highlights a histological slice from a progressing carious lesion. Specifically, the consultant discusses the importance of a translucent zone identified histologically within the dentine. A fellow colleague asks what this zone represents.
A - The canes-infected zone
B - The zone of hypermineralised dentine known as tubular sclerosis
C - The zone of hypermineralized surface enamel under which the carious process takes place
D - The zone of sound dentine immediately adjacent to the pulp complex
E - The zone of subsurface caries spread along the amelodentina
B - The zone of hypermineralised dentine known as tubular sclerosis
A foundation dentist is conducting an RCT on the lower right second premolar of a 26 year-old. woman. Whilst irrigating with chlorhexidine, she notes that the concentration is only 0.2% and asks her nurse for an alternative irrigant. The nurse goes to see the foundation trainer to see if they can borrow their sodium hypochlorite. The foundation trainer says that it is not advisable to use both solutions concomitantly because it might affect overall bacterial decontamination
What is the single main reason for this advice?
A - A precipitate is produced, which can block dentinal tubules from further irrigant effects
B - A reaction between the irrigants results in the production of a bacterial growth factor
C - Adjunctive sodium hypochlorite has no clinical benefits over chlorhexidine alone
D - The combination of solutions causes selective decontamination and
overgrowth of the more pathogenic bacteria
E. - The residual film produced causes degradation of gutta percha, allowing bacterial leakage
A - A precipitate is produced, which can block dentinal tubules from further irrigant effects
A 17-year-old adolescent man Is referred for root canal treatment an upper central incisor with an immature apex. The tooth is
non-vital and shows comparable root length to the contralateral incisor. Which is the single most appropriate technique to endodontically treat
his tooth?
A - Apexification with repeated dressings of non-setting calcium hydroxide
B - Apical plug formation with bioceramic material
C - Cvek pulpotomy
D - Endodontic surgery
E - Regenerative endodontic procedures
B - Apical plug formation with bioceramic material such as MTA.
MTA can cause discoloration of the tooth over time.
Keywords: immature apex, comparable root length
A 28-year-old man is having an obturation of a permanent / upper central incisor. A heated plugger (e.g. System-B) is being used during the ‘downpack’. Which is the single most appropriate description of the obturation technique being used?
A Carrier-based thermoplasticized technique
B Cold lateral condensation
C Single cone obturation
D Thermoplasticized injection technique
E Warm vertical compaction
A 47-year-old man is having RCT on his upper first molar, which has curved roots. Following coronal preparation of the mesiobuccal canal, an electronic apex locator (EAL) is used and provides a reproducible reading. This is 2 mm shorter than the ext mated working length (EWL) from the preoperative radiograph. What is the single most appropriate initial management
A - Obturate to the EWL and review
B - Obturate to the EWL, followed by apicectomy
C - Prepare using the reading of the EAL
D - Take a new radiograph to check for potential perforations
E - Take a parallax technique radiograph of the molar to identify the apex
C - Prepare using the reading of the EAL
A 43-year-old woman has pain from a lower central incisor that has previously received root canal treatment. Radiographically, a small, diffuse periapical lesion is present, but the obturation follows the root anatomy and appears adequate. A parallax radiograph indicates asymmetrical distribution of the obturation. What is the single most likely cause of failure?
A - Cyst formation
B - Missed canal
C - Perforation
D - Root fracture
E - Transportation of the apex
B - missed canal
Keywords - asymmetrical distribution of obturation
A 58-year-old woman with failed root canal treatment is seen in a new patient consultation clinic. A junior dental student asks about the process of root canal failure. She is aware that certain bacteria have significant dentine adherence capabilities and can survive harsh environments by demineralizing dentine and degrading collagen. Which is the single most likely causative organism in this scenario?
A - Aggregatibacter actinomycetemcomitans (Aa)
B - Enterococcus foecalis
C - Neisseria gonorrhoeae
D - Prevotella intermedia
E - Streptococcus mutans
B - Entero Foecalis
Keywords - harsh environment, failed RCT
A 23-year-old man has discomfort from his upper left first premolar but is keen to save it, if at all possible, Clinically, the tooth has deficient crown margins but otherwise appears OK. A cone beam computed tomography (CBCT) scan shows a missed palatal canal, a well-obturated buccal canal, and a periapical lesion. What is the single most appropriate management to save the tooth?
A - Antibiotics, a new crown, and monitoring of the apical lesion
B - Apicectomy and a new crown
C - Extraction
D - Obturate the palatal canal and new crown
E - Root canal retreatment and new crown
E - Root canal retreatment and new crown
Keywords - missed palatal canal, deficient crown margin
A 36-year-old man is having the restoration of a recently endodontically treated permanent molar tooth. Only the palatal wall remains in its entirety, but there is 2 mm of supra-gingival dentine elsewhere. What is the single most appropriate method to retain the core? * *
A - Multiple dentine pins
B - Nayyar core
C - Post-preparation in the mesiobuccal canal
D - Post-preparation in the palatal canal
E - Split post-technique
B - Nayyar core
