NBDE Dental Anatomy and Occlusion 5

Question 1

The primary function of the contact areas between adjacent teeth is to:

Accepted Answer

Protect the interdental papilla and maintain arch stability

Answer

Proximal contact areas protect the underlying interdental papilla from food impaction and maintain the position and stability of teeth in the arch.

Question 2

Which statement about the mandibular canine is TRUE compared to the maxillary canine?

Accepted Answer

Its crown is narrower mesiodistally

Answer

The mandibular canine has a narrower mesiodistal crown width compared to the maxillary canine, giving it a more slender appearance.

Question 3

In a Class I molar relationship, the mesiobuccal cusp of the maxillary first molar occludes:

Accepted Answer

In the buccal groove of the mandibular first molar

Answer

In Class I occlusion, the mesiobuccal cusp of the maxillary first molar occludes in the buccal groove of the mandibular first molar.

Question 4

Wear facets on the anterior teeth that do not match any opposing tooth surface in centric occlusion are most indicative of:

Accepted Answer

Parafunctional excursive contact (bruxism)

Answer

Non-centric wear facets that are shiny, flat, and match an opposing surface in excursion indicate parafunction (bruxism) during lateral or protrusive movements.

Question 5

The Frankfort horizontal plane is used in cephalometrics and is defined by which landmarks?

Accepted Answer

Porion, orbitale, and the midsagittal plane

Answer

The Frankfort horizontal plane is defined by the porion (top of the external auditory meatus) and the orbitale (lowest point of the orbital rim), oriented parallel to the floor.

NBDE - National Board Dental Examination Practice Test

NBDE - National Board Dental Examination Practice Test

NBDE Dental Anatomy and Occlusion 5