NBDE MCQ 3

Question 1

The canine eminence is formed by the root prominence of which tooth?

Accepted Answer

Maxillary canine

Answer

The maxillary canine has the longest root in the dentition, creating a prominent bony ridge called the canine eminence on the anterior maxilla.

Question 2

Which type of hypersensitivity reaction is responsible for allergic contact stomatitis from dental materials?

Accepted Answer

Type IV (cell-mediated)

Answer

Allergic contact stomatitis is a Type IV delayed hypersensitivity reaction mediated by sensitized T-lymphocytes reacting to haptens from dental materials.

Question 3

During mandibular nerve block, the needle tip should be positioned adjacent to which structure?

Accepted Answer

Mandibular foramen

Answer

The inferior alveolar nerve block targets the mandibular foramen on the medial ramus where the inferior alveolar nerve enters the mandibular canal.

Question 4

A white, non-removable plaque-like lesion of the oral mucosa that cannot be characterized as any other condition is called:

Accepted Answer

Leukoplakia

Answer

Leukoplakia is a clinical diagnosis of exclusion — a white patch that cannot be scraped off and cannot be identified as another specific lesion, with malignant potential.

Question 5

The working length in endodontic treatment is measured to:

Accepted Answer

The minor constriction (apical constriction)

Answer

Working length is established to the apical constriction (minor foramen), typically 0.5–1 mm from the radiographic apex, to preserve the apical seal.

NBDE - National Board Dental Examination Practice Test

NBDE - National Board Dental Examination Practice Test

NBDE MCQ 3