2010 Released Qs And Ans12

Front 1

A vital canine is to be used as the anterior
abutment of a four unit fixed partial
denture and it has 2mm remaining coronal
tooth structure. The most acceptable
foundation restoration would be
A. a bonded amalgam.
B. a pin retained amalgam core buildup.
C. a pin retained composite resin core
build-up.
D. intentional devitalization followed by
a post and core restoration.

Back 1

D. intentional devitalization followed by
a post and core restoration.

Front 2

If a cast is tripoded it serves as a useful
method of
A. determining the path of insertion.
B. locating unfavorable tissue
undercuts.
C. locating the height of contour.
D. returning the cast to the surveyor.

Back 2

D. returning the cast to the surveyor.

Front 3

The higher modulus of elasticity of a
chromium-cobalt-nickel alloy, compared
to a Type IV gold alloy, means that
chromium-cobalt-nickel partial denture
clasp will require
A. a heavier cross section for a clasp
arm.
B. a shorter retentive arm.
C. more taper.
D. a shallower undercut.

Back 3

D. a shallower undercut.

Front 4

High humidity in a room where zinc oxide
and eugenol impression paste is being
mixed will
A. increase the setting time.
B. not affect the setting.
C. prevent any setting.
D. decrease the setting time.

Back 4

D. decrease the setting time.

Front 5

The addition of platinum to a dental gold
alloy results in increased
1. strength.
2. hardness.
3. melting point.
4. resistance to corrosion.

Back 5

E. All of the above.

Front 6

The main purpose of flux in soldering is to
A. dissolve surface oxides and prevent
further oxidation.
B. prevent recrystallization and grain
growth.
C. prevent oxidation and lower the
melting range of the solder.
D. dissolve surface oxides and lower the
melting range.

Back 6

A. dissolve surface oxides and prevent
further oxidation.

Front 7

While the teeth are set in wax, dentures
are tried in to
A. verify the maxillomandibular
records.
B. verify the vertical dimension of
occlusion.
C. evaluate esthetics.
D. All of the above.

Back 7

D. All of the above.

Front 8

During the setting phase, a dental stone
mixture will exhibit
A. expansion.
B. contraction.
C. loss in compressive strength.
D. gain in moisture content

Back 8

A. expansion.

Front 9

Heated impression modeling compound is
"tempered" in warm water before
placement in the mouth in order to
A. avoid burning the soft tissues.
B. reduce contraction error.
C. initiate a chemical reaction.
D. minimize distortion.

Back 9

A. avoid burning the soft tissues.

Front 10

Prior to pouring a stone model, the
immersion of a hydrocolloid impression in
2~percent potassium sulphate for
2~to~5~minutes will
A. retard the set.
B. accelerate the set.
C. inhibit the formation of bubbles.
D. prevent distortion of the hydrocolloid
material.

Back 10

B. accelerate the set.

Front 11

Which of the following prevents distortion
of a reversible hydrocolloid impression
material?
A. Slow removal from undercuts.
B. Storage in 100 percent humidity for
30 minutes.
C. Storage in air.
D. Storage in 2 percent solution of
potassium sulfate for 60 minutes.

Back 11

B. Storage in 100 percent humidity for
30 minutes.

Front 12

The exudate produced on the surface of an
alginate impression through syneresis acts
as
A. a lubricant between the impression
material and the gypsum cast.
B. a medium that aids in producing
distinct details on the surface of the
resultant gypsum cast.
C. a medium that aids in producing a
hard surface on the gypsum cast.
D. None of the above.

Back 12

D. None of the above.

Front 13

After cementation of a fixed bridge, the
patient should be advised to
1. avoid hot liquids.
2. stimulate the gingival tissue with
massage.
3. use dental floss under the pontic.
4. return for periodic examination.
5. avoid sticky foods.

Back 13

2. stimulate the gingival tissue with
massage.
3. use dental floss under the pontic.
4. return for periodic examination

Front 14

The major disadvantage of zinc phosphate
used to cement crowns is the
A. development of heat during setting.
B. pulp irritation.
C. lack of edge strength.
D. low crushing strength.

Back 14

B. pulp irritation.

Front 15

A pontic replacing a mandibular first
molar should be designed so that
1. it seals the muco-gingival field.
2. it has opened gingival embrasures.
3. it conceals the porcelain to metal
junction on its gingival surface.
4. its gingival surface is convex in all
directions.

Back 15

2. it has opened gingival embrasures
4. its gingival surface is convex in all
directions.

Front 16

A fixed bridge pontic should
1. restore tooth function.
2. reduce thermal conductivity.
3. be biologically acceptable.
4. reduce galvanic reactions between
abutments and other restorations.
5. restore aesthetics.

Back 16

1. restore tooth function.
3. be biologically acceptable.
5. restore aesthetics.

Front 17

In a "cuspid guided occlusion"
A. the teeth on the non-working side
make contact on lateral excursions.
B. the teeth on the working side make
contact on lateral excursions.
C. the posterior teeth make no contact
on lateral excursions on the working
side.
D. None of the above.

Back 17

C. the posterior teeth make no contact
on lateral excursions on the working
side.

Front 18

An epinephrine-containing retraction cord
has the potential of
A. interfering with the setting of the
impression material.
B. causing tissue necrosis.
C. producing a systemic reaction.
D. discolouring gingival tissue.

Back 18

C. producing a systemic reaction.

Front 19

A cast post and core is used to
1. provide intraradicular venting.
2. strengthen a weakened tooth.
3. redirect the forces of occlusion.
4. provide retention for a cast crown.

Back 19

4. provide retention for a cast crown

Front 20

The gingival margin of the preparation for
a full crown on a posterior tooth, with a
clinical crown that satisfies the
requirements for retention and resistance,
should be placed
A. 0.5mm subgingivally.
B. on the enamel.
C. at least 1mm supragingivally.
D. at the cemento-enamel junction.
E. at the gingival margin.

Back 20

C. at least 1mm supragingivally.

Front 21

In treatment planning for a fixed bridge,
the necessary clinical data should include
1. an assessment of any discrepancy
between centric occlusion and centric
relation.
2. the type of impression materials to be
used.
3. an evaluation of the forces of
mastication.
4. the aesthetic considerations.

Back 21

1. an assessment of any discrepancy
between centric occlusion and centric
relation.
3. an evaluation of the forces of
mastication.
4. the aesthetic considerations.

Front 22

Adjustment of the occlusal plane of
natural teeth opposed by a complete or
partial denture should be completed
A. after the teeth have been set on the
trial denture.
B. immediately after making the final
casts.
C. upon delivery of the denture.
D. after the diagnosis and treatment plan
has been established.

Back 22

D. after the diagnosis and treatment plan
has been established.

Front 23

During the fabrication of new complete
dentures, which of the following can be
modified to achieve the desired occlusion?
1. The compensating curve.
2. The orientation of the occlusal plane
3. The cusp inclination.
4. The condylar inclination.

Back 23

1. The compensating curve.
2. The orientation of the occlusal plane
3. The cusp inclination.

Front 24

At his first post insertion appointment, a
patient with a new removable partial
denture complains of a tender abutment
tooth. The most likely cause is
A. overextended borders of the partial.
B. inadequate polishing of the
framework.
C. improper path of insertion.
D. the occlusion.

Back 24

D. the occlusion.

Front 25

Wrought gold alloy clasps are superior to
cast gold clasps of the same crosssectional
area because they
1. exhibit greater flexibility.
2. are coarser grained.
3. are more accurately adapted to the
tooth.
4. have a higher proportional limit.

Back 25

1. exhibit greater flexibility.
4. have a higher proportional limit.

Front 26

Abutment teeth for a removable partial
denture may be best preserved by
A. splinting with adjacent teeth.
B. Full coverage wth veneer crowns.
C. prosthesis design.
D. all of the above.

Back 26

C. prosthesis design

Front 27

In removable partial denture design, the
surface of the abutment tooth most often
altered to provide clasp reciprocity is
A. mesial.
B. distal.
C. occlusal.
D. buccal.
E. lingual.

Back 27

E. lingual.

Front 28

In the design of a removable partial
denture, guiding planes are made
A. parallel to the long axis of the tooth.
B. parallel to the path of insertion.
C. at a right angle to the occlusal plane.
D. at a right angle to the major
connector.

Back 28

B. parallel to the path of insertion.

Front 29

Rests on terminal abutment teeth for a cast
metal removable partial denture provide
A. primary retention.
B. indirect retention.
C. occlusal force transmission.
D. lateral force transmission.

Back 29

C. occlusal force transmission.

Front 30

For a removable partial denture, a metal
base is preferred to an acrylic base
because metal is
A. more hygienic.
B. stronger.
C. less irritating.
D. a better thermal conductor.
E. All of the above.

Back 30

E. All of the above.

Front 31

Compared with zinc-phosphate cement,
polycarboxylate cement has
A. longer working time.
B. lower film thickness.
C. increased compressive strength.
D. superior biologic compatibility.

Back 31

D. superior biologic compatibility.

Front 32

Which of the following should be checked
first when a cast gold crown that fits on its
die cannot be seated on its abutment?
A. The occlusal contacts.
B. The taper of the preparation.
C. The proximal contacts.
D. The impression used to pour the cast.

Back 32

C. The proximal contacts.

Front 33

In the preparation of gypsum products, an
increase in the water/powder ratio will
A. increase the surface hardness.
B. increase the compressive strength.
C. accelerate the setting reaction.
D. None of the above.

Back 33

D. None of the above

Front 34

Which of the following are effects of cold
working a metal?
1. Increase in ductility.
2. Decrease in ductility.
3. Increase in hardness.
4. Increase in resistance to corrosion.

Back 34

2. Decrease in ductility.
3. Increase in hardness.

Front 35

Reversible hydrocolloids transform from
sol to gel and gel to sol as a function of the
A. concentration of the fillers and
plasticizers.
B. percent composition by weight of
water.
C. concentration of potassium sulfate.
D. temperature.

Back 35

D. temperature.

Front 36

A facebow is used to record the
1. vertical dimension of occlusion.
2. inter-condylar distance.
3. horizontal condylar inclination.
4. relationship of the maxilla to the
hinge axis

Back 36

2. inter-condylar distance.
4. relationship of the maxilla to the
hinge axis

Front 37

Denture stomatitis can be associated with
A. candida albicans infection.
B. xerostomia.
C. inadequate denture hygiene.
D. ill-fitting dentures.
E. All of the above

Back 37

E. All of the above

Front 38

Xerostomia can be associated with
A. hormonal imbalance.
B. hypertension and anxiety.
C. adverse effects of medication.
D. emotional problems.
E. All of the above.

Back 38

E. All of the above.

Front 39

Unsupported, hyperplastic tissue in an
edentulous maxilla is most often found
A. near the tuberosities.
B. in the vault.
C. in the anterior segment of the arch.
D. None of the above.

Back 39

C. in the anterior segment of the arch.

Front 40

Following the insertion of complete
dentures, a generalized soreness over the
entire mandibular alveolar ridge can be
caused by
A. Inadequate interocclusal distance.
B. impingement on the buccal frenum.
C. high muscle attachments.
D. excess border thickness.

Back 40

A. Inadequate interocclusal distance.

Front 41

When a removable partial denture is
fabricated to occlude with natural teeth,
the occlusal form of the artificial teeth is
influenced by the
A. endodontic condition of the abutment
teeth.
B. occlusal form of the remaining teeth.
C. need to produce a fully balanced
occlusion.
D. None of the above.

Back 41

B. occlusal form of the remaining teeth.

Front 42

When a partial denture is to be constructed
where occlusal adjustment of the natural
teeth is required, this should be performed
A. prior to taking the final impressions.
B. after the restoration is completed.
C. prior to registering centric relation
but after final impression taking.
D. after the framework has been
constructed.

Back 42

A. prior to taking the final impressions.

Front 43

A removable partial denture rest should
A. be extended for retention.
B. increase retention of the partial
denture.
C. direct forces parallel to the long axis
of the abutment.
D. be located on a centric contact.

Back 43

C. direct forces parallel to the long axis
of the abutment.

Front 44

For removable partial dentures, tilting of
the cast during surveying procedures alters
the
1. path of insertion.
2. direction of dislodging forces.
3. position of the survey line in relation
to the horizontal plane.
4. location of the undercut and nonundercut
areas of each tooth.

Back 44

1. path of insertion.
3. position of the survey line in relation
to the horizontal plane.
4. location of the undercut and nonundercut
areas of each tooth.

Front 45

Bar clasp and circumferential clasp arms
are similar in that both
1. terminate in a retentive undercut lying
gingival to the height of contour.
2. originate from the framework and
approach the tooth undercut area from
a gingival direction.
3. provide retention by the resistance of
metal to deformation rather than
frictional resistance of parallel walls.
4. originate above the height of contour,
traverse a portion of the suprabulge
and approach the tooth undercut from
an occlusal direction.

Back 45

1. terminate in a retentive undercut lying
gingival to the height of contour.
3. provide retention by the resistance of
metal to deformation rather than
frictional resistance of parallel walls.

Front 46

A removable partial denture rest should be
placed on the lingual surface of a canine
rather than on the incisal surface because
A. less leverage is exerted against the
tooth by the rest.
B. the enamel is thicker on the lingual
surface.
C. visibility and access are better.
D. the cingulum of the canine provides a
natural recess.

Back 46

A. less leverage is exerted against the
tooth by the rest.

Front 47

The crownçroot ratio is
1. the comparison of the length of root
retained in bone to the amount of
tooth external to it.
2. an important factor in abutment
tooth selection.
3. determined from radiographs.
4. determined during surveying of the
diagnostic cast.

Back 47

1. the comparison of the length of root
retained in bone to the amount of
tooth external to it.
2. an important factor in abutment
tooth selection.
3. determined from radiographs.

Front 48

In an edentulous maxilla, the direction of
resorption of the alveolar ridge is
A. upward and palatally.
B. upward and facially.
C. uniform in all directions.
D. upward only.

Back 48

A. upward and palatally.

Front 49

A metal in the wrought condition differs
from the same metal in the cast condition
in that
A. the grains are deformed and
elongated.
B. the yield strength and hardness are
increased.
C. if heated sufficiently,
recrystallization can occur.
D. All of the above.

Back 49

D. All of the above.

Front 50

Dental porcelain has
1. low compressive strength.
2. high hardness.
3. high tensile strength.
4. low impact strength.

Back 50

2. high hardness.
4. low impact strength.