NBDE Prosthodontics and Operative Dentistry 3

Question 1

The major connector for a maxillary removable partial denture should be located at least how far from the free gingival margin?

Accepted Answer

6 mm

Answer

The major connector must be placed at least 6 mm from the free gingival margin to avoid impingement on gingival tissue.

Question 2

Which material demonstrates the highest fracture toughness among current all-ceramic crown systems?

Accepted Answer

Zirconia (Y-TZP)

Answer

Zirconia (yttria-stabilized tetragonal zirconia polycrystal) has the highest fracture toughness of current all-ceramic materials due to transformation toughening.

Question 3

In operative dentistry, the term 'convenience form' refers to:

Accepted Answer

The shape that allows access for instruments and insertion of the restoration

Answer

Convenience form involves modifications to the cavity preparation that allow adequate access for instruments and proper placement of the restorative material.

Question 4

The retentive arm of a circumferential clasp for a removable partial denture engages the undercut at what relationship to the height of contour?

Accepted Answer

Below the height of contour

Answer

The retentive tip of the clasp must be positioned below the height of contour (in the undercut zone) to provide retention through clasp flexion.

Question 5

When evaluating a patient for implant-supported prosthetics, the minimum bone height required above the inferior alveolar canal for a standard implant is:

Accepted Answer

10 mm

Answer

A minimum of 10 mm of bone height above the inferior alveolar canal is generally required for safe placement of a standard-length dental implant.

NBDE - National Board Dental Examination Practice Test

NBDE - National Board Dental Examination Practice Test

NBDE Prosthodontics and Operative Dentistry 3