NBDE Part II -2006 Exam C| QUESTIONS
AND ANSWERS| 100% CORRECT
Addition cured silicones (polyvinyl siloxanes) are often the material of choice for
impressions for fixed restorations. Each of the following is true about these
materials EXCEPT one. Which one is this EXCEPTION?
A. Give off ethyl alcohol during their setting reaction
B. Can be poured more than once and still remain accurate
C. Can be poured after 24 hours and still remain accurate
D. Rebound from undercuts without permanent deformation
E. May release hydrogen gas during setting Correct Answer: A. Give off ethyl
alcohol during their setting reaction
Which of the following describes the laterotrusive movement (Bennett angle)?
A. It is the angle that is formed by the non-working condyle and the sagittal plane
during lateral movements.
B. It is the angle that is formed by the condyle and the horizontal plane during
protrusive movements.
C. It is the difference in condylar inclination between protrusive and lateral
movements.
D. It is the difference between the condylar and incisal inclinations. Correct
Answer: A. It is the angle that is formed by the non-working condyle and the
sagittal plane during lateral movements.
In selecting an impression tray for a preliminary maxillary impression, how far
should the tray extend posteriorly?
A. To the tuberosity
B. To the fovea palatine
C. Beyond the vibrating line
D. To the pterygomaxillary notches Correct Answer: C. Beyond the vibrating line
,Occlusal morphology is determined by the height of the cusp and the depth of the
fossa. Each of the following is a vertical component of this morphology EXCEPT
one. Which one is this EXCEPTION?
A. Side shift
B. Intercondylar distance
C. Curve of Spee
D. Horizontal overlap of anterior teeth Correct Answer: B. Intercondylar distance
Why is it advisable to dispense the liquid component of cement immediately
before mixing?
A. To avoid absorption of moisture from the air
B. To avoid spreading over a large area of the slab
C. To allow tempering of the powder by the mixing slab
D. To reduce the temperature influence of the mixing slab
E. To prevent evaporation of the volatile components Correct Answer: E. To
prevent evaporation of the volatile components
Which of the following groups of muscles are influential in molding the lingual
border of the final mandibular impression for a complete denture?
A. Hyoglossus, mylohyoid, medial pterygoid, digastric
B. Mylohyoid, styloglossus, medial pterygoid, depressor anguloris
C. Palatoglossus, superior pharyngeal constrictor, mylohyoid, genioglossus
D. Genioglossus, mylohyoid, middle pharyngeal constrictor, posterior belly of the
digastric Correct Answer: C. Palatoglossus, superior pharyngeal constrictor,
mylohyoid, genioglossus
Which of the following represents the MOST likely cause of plastic denture teeth
being dislodged from the acrylic resin of the denture base?
A. Excessive occlusal forces applied
B. Occlusal surfaces adjusted excessively
C. Retentive undercuts not placed in the teeth
D. Residual wax on teeth when processing Correct Answer: D. Residual wax on
teeth when processing
, Which of the following represents the optimal incisal reduction for a metal-
ceramic crown preparation?
A. 1.0 mm
B. 1.5 mm
C. 2.0 mm
D. 2.5 mm
E. 3.0 mm Correct Answer: C. 2.0 mm
All-ceramic crowns should NOT be used for patients who are associated with each
of the following conditions EXCEPT one. Which one is the EXCEPTION?
A. Severe bruxism
B. Previous history of ceramic crown fractures
C. Amalgam restorations with marginal breakdown
D. Extensive wear of tooth structure or restorations Correct Answer: C. Amalgam
restorations with marginal breakdown
A static positional record can be used to adjust posterior articulator controls. In
order to set the left condylar inclination and the left sideshift, which of the
following are minimally required?
A. Protrusive checkbite in incisal edge-to-edge position
B. Protrusive checkbite in extreme protrusive position
C. Right lateral excursive record
D. Left lateral excursive record Correct Answer: C. Right lateral excursive record
The long-term prognosis of a single-abutment cantilever fixed partial denture may
be compromised, because forces are best tolerated by the periodontal supporting
structures when directed in the long axes of the teeth.
A. Both the statement and the reason are correct and related.
B. Both the statement and the reason are correct but NOT related.
C. The statement is correct, but the reason is NOT.
D. The statement is NOT correct, but the reason is correct.
AND ANSWERS| 100% CORRECT
Addition cured silicones (polyvinyl siloxanes) are often the material of choice for
impressions for fixed restorations. Each of the following is true about these
materials EXCEPT one. Which one is this EXCEPTION?
A. Give off ethyl alcohol during their setting reaction
B. Can be poured more than once and still remain accurate
C. Can be poured after 24 hours and still remain accurate
D. Rebound from undercuts without permanent deformation
E. May release hydrogen gas during setting Correct Answer: A. Give off ethyl
alcohol during their setting reaction
Which of the following describes the laterotrusive movement (Bennett angle)?
A. It is the angle that is formed by the non-working condyle and the sagittal plane
during lateral movements.
B. It is the angle that is formed by the condyle and the horizontal plane during
protrusive movements.
C. It is the difference in condylar inclination between protrusive and lateral
movements.
D. It is the difference between the condylar and incisal inclinations. Correct
Answer: A. It is the angle that is formed by the non-working condyle and the
sagittal plane during lateral movements.
In selecting an impression tray for a preliminary maxillary impression, how far
should the tray extend posteriorly?
A. To the tuberosity
B. To the fovea palatine
C. Beyond the vibrating line
D. To the pterygomaxillary notches Correct Answer: C. Beyond the vibrating line
,Occlusal morphology is determined by the height of the cusp and the depth of the
fossa. Each of the following is a vertical component of this morphology EXCEPT
one. Which one is this EXCEPTION?
A. Side shift
B. Intercondylar distance
C. Curve of Spee
D. Horizontal overlap of anterior teeth Correct Answer: B. Intercondylar distance
Why is it advisable to dispense the liquid component of cement immediately
before mixing?
A. To avoid absorption of moisture from the air
B. To avoid spreading over a large area of the slab
C. To allow tempering of the powder by the mixing slab
D. To reduce the temperature influence of the mixing slab
E. To prevent evaporation of the volatile components Correct Answer: E. To
prevent evaporation of the volatile components
Which of the following groups of muscles are influential in molding the lingual
border of the final mandibular impression for a complete denture?
A. Hyoglossus, mylohyoid, medial pterygoid, digastric
B. Mylohyoid, styloglossus, medial pterygoid, depressor anguloris
C. Palatoglossus, superior pharyngeal constrictor, mylohyoid, genioglossus
D. Genioglossus, mylohyoid, middle pharyngeal constrictor, posterior belly of the
digastric Correct Answer: C. Palatoglossus, superior pharyngeal constrictor,
mylohyoid, genioglossus
Which of the following represents the MOST likely cause of plastic denture teeth
being dislodged from the acrylic resin of the denture base?
A. Excessive occlusal forces applied
B. Occlusal surfaces adjusted excessively
C. Retentive undercuts not placed in the teeth
D. Residual wax on teeth when processing Correct Answer: D. Residual wax on
teeth when processing
, Which of the following represents the optimal incisal reduction for a metal-
ceramic crown preparation?
A. 1.0 mm
B. 1.5 mm
C. 2.0 mm
D. 2.5 mm
E. 3.0 mm Correct Answer: C. 2.0 mm
All-ceramic crowns should NOT be used for patients who are associated with each
of the following conditions EXCEPT one. Which one is the EXCEPTION?
A. Severe bruxism
B. Previous history of ceramic crown fractures
C. Amalgam restorations with marginal breakdown
D. Extensive wear of tooth structure or restorations Correct Answer: C. Amalgam
restorations with marginal breakdown
A static positional record can be used to adjust posterior articulator controls. In
order to set the left condylar inclination and the left sideshift, which of the
following are minimally required?
A. Protrusive checkbite in incisal edge-to-edge position
B. Protrusive checkbite in extreme protrusive position
C. Right lateral excursive record
D. Left lateral excursive record Correct Answer: C. Right lateral excursive record
The long-term prognosis of a single-abutment cantilever fixed partial denture may
be compromised, because forces are best tolerated by the periodontal supporting
structures when directed in the long axes of the teeth.
A. Both the statement and the reason are correct and related.
B. Both the statement and the reason are correct but NOT related.
C. The statement is correct, but the reason is NOT.
D. The statement is NOT correct, but the reason is correct.
