MJDF Part 1 - Membership of Joint Dental Faculties Prosthodontics and Tooth Replacement Questions and Answers

Question 1

An elderly patient returns one week after the insertion of new complete dentures, complaining that the lower denture lifts when they open their mouth wide or protrude their tongue.
Which of the following is the most likely cause of this instability?

Accepted Answer

C. The lingual flange of the lower denture is overextended.

Answer

A. The occlusal vertical dimension is too high.

Answer

B. The posterior palatal seal of the upper denture is inadequate.

Answer

D. The posterior teeth are set outside of the neutral zone.

Question 2

A 22-year-old patient with a congenitally missing, unrestored upper lateral incisor (UR2) is considering a fixed replacement. The adjacent canine and central incisor are sound. According to UK best practice guidelines, which of the following is the most suitable design for a long-term successful resin-retained bridge?

Accepted Answer

A. A cantilever design with a single retainer on the canine.

Answer

B. A fixed-fixed design with retainers on both the canine and central incisor.

Answer

C. A design with significant tooth preparation to create parallel guide planes.

Answer

D. A design luted with a conventional glass ionomer cement.

Question 3

A patient is missing the following teeth: UL4, UL5, UL6, UR4, and UR5. All other teeth are present and sound. According to the Kennedy classification system, how should this dental arch be classified?

Accepted Answer

D. Kennedy Class III Modification 1.

Answer

A. Kennedy Class II Modification 1.

Answer

B. Kennedy Class I.

Answer

C. Kennedy Class IV.

Question 4

A dentist is taking a definitive impression for a crown on the LR6 using a polyvinyl siloxane (addition-cured silicone) material. The dentist is wearing standard latex examination gloves while mixing the putty. Which of the following issues is most likely to occur?

Accepted Answer

A. Sulphur compounds in the latex gloves may inhibit the polymerisation of the impression material.

Answer

B. The material will experience significant dimensional shrinkage due to the latex.

Answer

C. The latex will accelerate the setting reaction, reducing the working time.

Answer

D. The impression material will become excessively rigid and difficult to remove from the mouth.

Question 5

When designing a cobalt-chromium removable partial denture, what is the primary function of an occlusal rest?

Accepted Answer

D. To transmit occlusal forces along the long axes of the abutment teeth.

Answer

A. To provide resistance to lateral displacement.

Answer

B. To engage an undercut and resist vertical dislodgement.

Answer

C. To link components on one side of the arch to the other.

Question 6

During the jaw registration stage for new complete dentures, the clinician guides the patient's mandible into centric relation. What is the main clinical significance of recording this position?

Accepted Answer

B. It is a repeatable reference position from which to build the occlusion.

Answer

A. It establishes the patient's desired smile line and tooth display.

Answer

C. It represents the position of maximum tooth intercuspation.

Answer

D. It is primarily used to select the correct size and shade of the denture teeth.