- Category: Endodontics
- Aim: Revising for NBDE Part II
- Questions: 54
- Hint: No
- Mutiple Opportunites: No
- Time Limit: No
- Answer Explaining: Yes
Which of the following tests is the least useful in endodontic diagnosis of children?
Electric pulp test
Resistance of the host
Virulence of the organisms
Number of organisms present
Both A and B only
All of the choices are true
Loss of root vitality
Plastic deformation of dentin
Destruction of the coronal architecture
Which of the following is the main side effect of bleaching an endodontically treated tooth?
External cervical resorption
Demineralization of tooth structure
Immediate attempt to remove the instrument.
Stop canal instrumentation, do not attempt removal, and obturate.
Attempt to bypass the obstructed instrument.
Both A and C are options.
Irreversible pulpitis pain in which of the following sites is most likely to radiate to the ear?
Acute periradicular periodontitis
Chronic periradicular periodontitis
Gutta-percha filling followed by root-end surgery
Pulpectomy immediately and splint.
Splint and observe.
Do nothing and follow-up in 10 to 14 days.
Treat with conventional root canal therapy.
Antibiotics are not needed.
The sinus tract should heal in 2 to 4 weeks after conventional root canal therapy.
If the tract persists post-root canal therapy, do root-end surgery with root-end filling.
All of the above choices are true.
0.2-mm increase in diameter per 1-mm increase in length
0.02-mm increase in diameter per 1-mm increase in length
0.2-mm increase in diameter per 2-mm increase in length
0.02-mm increase in diameter per 2-mm increase in length
The primary purpose of the post is to retain a core in a tooth with extensive loss of coronal structure.
The need for a post is dictated by the amount of remaining coronal tooth structure.
Posts reinforce the tooth and help to prevent vertical fractures.
At least 4 to 5 mm of remaining gutta-percha after post space preparation is recommended.
To avoid incising over a bony protuberance
To obtain maximum access to the surgical site
To maintain an adequate blood supply to the reflected tissue
To aid in complete reflection
How should a vital second permanent molar with a 2.0-mm exposure on a 12-year-old patient be treated?
Direct pulp capping
Indirect pulp capping
Which of the following most likely applies to a cracked tooth?
The direction of the crack usually extends mesiodistally.
The direction of the crack usually extends faciolingually.
Radiographic exam is the best way to detect it.
A and C only.
B and C only.
Which perforation location has the best prognosis?
Coronal third of root
Apical third of root
Middle third of root
Two maxillary central incisors
Maxillary central and lateral incisors
Maxillary lateral and canine
Maxillary canine and first premolar
The benefits of endodontic treatment
The cost of endodontic treatment
The risks of endodontic treatment
It happens rarely in permanent teeth.
It appears as an asymmetrical “moth-eaten” lesion in radiographs.
Chronic pulpal inflammation is the primary cause.
Prompt endodontic therapy will stop the process.
First statement is true, second is false.
First statement is false, second is true.
Both statements are true.
Both statements are false.
A greater number of odontoblasts are present
Of incomplete development of nerve endings
An open apex allows for greater circulation
The root is shorter
Immediately attempt to remove the instrument.
Do not attempt removal and proceed to obturate.
Attempt to bypass the obstructed instrument.
Both A and C are options.
Calcium hydroxide pulpotomy
Delay for the purpose of re-evaluation
D. For decades, controversy has surrounded the validity of thermal and electric tests on traumatized teeth. Only generalized impressions may be gained from these tests subsequent to a traumatic injury. They are, in reality, sensitivity tests for nerve function and do not indicate the presence or absence of blood circulation within the pulp. It is assumed that subsequent to traumatic injury, the conduction capability of the nerve endings or sensory receptors is sufficiently deranged to inhibit the nerve impulse from an electric or thermal stimulus. This makes the traumatized tooth vulnerable to false negative readings from these tests.
Teeth that give a positive response at the initial examination cannot be assumed to be healthy or that they will continue to give a positive response over time. Teeth that yield a negative response or no response cannot be assumed to have necrotic pulps because they may give a positive response at later follow-up visits. It has been demonstrated that it may take as long as 9 months for normal blood flow to return to the coronal pulp of a traumatized, fully formed tooth. As circulation is restored, responsiveness to pulp tests returns.
That the apex has formed
Loss of periradicular lucency
No internal resorption
Continue instrumenting at the ledge. Although it may take some time, you will eventually bore your way to patency in the periodontal ligament space.
Immediately stop and fill to where the ledge begins.
Bind your irrigating needle in the canal and use short bursts of irrigant to loosen any debris blocking the canal. This will reopen the natural canal.
Prebend the tip of a small file, lubricate, and try to negotiate around the ledge.
Place citric acid or EDTA in the canal to soften the dentin. A small Gates Glidden or other rotary can be used to bypass the ledge.
Use a smaller instrument and get by the ledge.
Fill as far as you have reamed.
Use a small, round bur and remove the ¡edge.
Continue working gently with larger files to remove the ledge.
Which is not a property of sodium hypochlorite (NaOCl)?
Tissue dissolution at higher concentrations
Flotation of debris and lubrication
The major objectives of access preparation include all of the following except which one?
The attainment of direct, straight-line access to canal orifices.
The confirmation of clinical diagnosis.
The conservation of tooth structure.
The attainment of direct, straight-line access to the apical portion of the root.
What is the safest recommended intracoronal bleaching chemical?
Size of the defect.
Location of the defect.
Time elapsed between the perforation and its repair.
All of the choices are true.
Which one of the following cannot be observed on a conventional radiograph?
Canal calcification of tooth #15.
Buccal curvature of the mesial root of tooth #30.
Type of canals of tooth #21.
Open apex of tooth #8.
Electric pulp test
At what stage is endodontic treatment considered complete?
When a temporary restoration is placed and the rubber dam removed.
When canals are seared off and plugged.
When the coronal restoration is completed.
When the patient is asymptomatic.
A significant decrease in patient radiation
A more accurate image of the tooth’s dimensions
That it is easier to reproduce radiographs at similar angles to assess healing after treatment
The most accurate image of all the tooth’s dimensions and its relationship to surrounding anatomic structures
Multiple Water’s projections
Multiple angulated periapical radiographs in addition to a normal, parallel-angulated, periapical radiograph
A panoramic radiograph
A reverse Towne’s projection
The indications for periradicular surgery include all of the following except which one?
Procedural accidents during previous nonsurgical endodontic treatment.
Irretrievable separated files in the canals.
Failed nonsurgical endodontic treatment and persisting radiolucency.
Treatment for a nonrestorable tooth.
Calcification in the pulp chambers
Closed apices more than teeth with open apices
B. The indications for a direct pulp cap are (1) asymptomatic tooth; (2) with little or no hemorrhaging; (3) small (< 1 mm); and (4) welhisolated traumatic pulp exposure. It acts to stimulates the formation of a reparative dentin bridge over the exposure site and to preserve the underlying pulpal tissue. It is especially successful in immature teeth. Failure of direct pulp cap is indicated by (1) symptoms of pulpitis at any time; and (2) lack of vital pulp response after several weeks. Failures result in pulpal necrosis (continual pulpal insult), calcification of the pulp, or (rarely) internal resorption.
Direct pulp capping is primarily used on permanent teeth. (Not used often in primary teeth because the alkaline pH of calcium hydroxide.) It can irritate the pulp either mildly or (often) severely. With severe irritation, it increases the risk of internal resorption. With primary teeth, severe resorption is more common; in perma¬nent teeth, formation of reparative dentin occurs more often.
They persist and stimulate formulation of a granuloma.
They are eliminated by the natural defenses of the body.
They reenter and reinfect the sterile canal unless root-end surgery is performed.
They will have been eliminated by various medicaments that were used in the root canal.
Nonsurgical endodontic retreatment.
Recall the patient in another 6 months.
Surgical endodontic retreatment.
Features of focal sclerosing osteomyelitis often include:
A nonvital pulp test.
A history of recent restoration of the tooth in question.
A radiolucent lesion which, in time, becomes radiopaque.
None of the choices is true.
Vertical angle of the cone was increased
Vertical angle of the cone was decreased
X-ray head was angled from a distal position relative to the premolar
X-ray head was angled from a mesial position relative to the premolar
Larger unmyelinated nerve fibers with slower conduction velocities
Larger myelinated nerve fibers with faster conduction velocities
Smaller myelinated nerve fibers with slower conduction velocities
Smaller unmyelinated nerve fibers with faster conduction velocities
Which of the following can be viewed on a conventional radiograph?
Buccal curvature of roots
Calcification of canals
Remaining debris within the canal
No straight-line access
Normal mastication plus toothbrushing has driven microorganisms deep into tissues with subsequent pulp involvement at the apex.
During a general bacteremia, bacteria settled in this aggravated pulp and produced an acute pulpitis.
Repeated thermal shock from air and fluids getting into the deep pockets caused the pulpitis.
An accessory pulp canal in the gingival or the middle third of the root was in contact with the pockets.
Dissolve organic matter
Dissolve inorganic matter
Prevent sealer from extruding out of the canal space
It is less irritating
It has increased strength over other restorations
It provides a good seal
It is inexpensive
Pulpal anesthesia of the maxillary second and third molars.
Pulpal anesthesia of the maxillary first molar.
Pulpal anesthesia of the maxillary first and second premolars.
Pulpal anesthesia of the second premolar.