CDT Crown & Bridge Fabrication 2

Question 1

What is the primary purpose of a proximal contact in a fixed bridge pontic design?

Accepted Answer

To prevent food impaction and maintain arch integrity

Answer

Proximal contacts in bridge pontics prevent food impaction and help maintain the spatial integrity of the dental arch.

Question 2

Which alloy system is most susceptible to green corrosion (verdigris) when used in crown and bridge work?

Accepted Answer

Base-metal alloys containing copper

Answer

Base-metal alloys with high copper content are prone to green corrosion (verdigris) due to copper oxide formation in oral environments.

Question 3

When waxing a full-contour crown, the ideal buccolingual width of the occlusal table on a mandibular molar should be approximately what fraction of the total tooth width?

Accepted Answer

One-third

Answer

The occlusal table should be approximately one-third of the total buccolingual width to reduce lateral forces and preserve periodontium.

Question 4

During the soldering of a fixed partial denture, which flux type is appropriate for high-fusing base-metal alloys?

Accepted Answer

Fluoride-containing flux

Answer

Fluoride-containing fluxes are required for base-metal alloys because they effectively dissolve the tenacious chromium oxide layer that forms on these alloys.

Question 5

A 'working cast' in crown and bridge fabrication differs from a 'master cast' primarily because the working cast:

Accepted Answer

Has removable dies that can be separated from the cast

Answer

A working cast features individually removable dies so each preparation can be accessed independently while maintaining the full-arch relationship.

(CDT) Certified Dental Technicians Practice Test

(CDT) Certified Dental Technicians Practice Test

CDT Crown & Bridge Fabrication 2