2010 Released Qs And Ans13

Front 1

After processing, complete dentures on the
original stone casts are rearticulated in
order to correct occlusal disharmony
produced by
1. flasking and processing procedures.
2. strained jaw relation records.
3. errors in registering of centric jaw
relation.

Back 1

1. flasking and processing procedures.

Front 2

Dental polysulfide rubber impression
materials are polymerized with the
following initiator:
A. lead peroxide.
B. sodium peroxide.
C. carbon disulfide.
D. hydrogen peroxide.
E. phosphorus pentoxide.

Back 2

A. lead peroxide.

Front 3

The accuracy of the mercaptan polysulfide
and silicone rubber impression materials
A. is less than that of alginates.
B. is better than that of hydrocolloids.
C. is contra-indicated.
D. compares favorably with reversible
hydrocolloids.
E. is inversely proportional to
temperature and humidity.

Back 3

D. compares favorably with reversible
hydrocolloids.

Front 4

Which of the following structures affects
the thickness of the flange of a maxillary
complete denture?
A. Malar process.
B. Coronoid process.
C. Mylohyoid ridge.
D. Zygomatic process.
E. Genial tubercle.

Back 4

B. Coronoid process

Front 5

The form of the distobuccal border of a
mandibular denture is modified by
1. buccinator muscle.
2. masseter.
3. temporal tendon.
4. pterygomandibular raphe.
5. external oblique ridge.

Back 5

1. buccinator muscle.
2. masseter.

Front 6

Which of the following should be
evaluated for surgical removal before new
complete dentures are constructed?
A. Mandibular tori.
B. Epulis fissuratum.
C. Papillary hyperplasia.
D. Sharp, prominent mylohyoid ridges.
E. All of the above.

Back 6

E. All of the above.

Front 7

Upon examination of an edentulous
patient, it is observed that the tuberosities
contact the retromolar pads at the correct
occlusal vertical dimension. The treatment
of choice is to
A. reduce the retromolar pads surgically
to provide the necessary clearance.
B. reduce the tuberosities surgically to
provide the necessary clearance.
C. construct new dentures at an
increased occlusal vertical dimension
to gain the necessary clearance.
D. proceed with construction of the
denture and reduce the posterior
extension of the mandibular denture
to eliminate interferences.

Back 7

B. reduce the tuberosities surgically to
provide the necessary clearance.

Front 8

Most zinc-oxide-eugenol cements are not
suitable for permanent cementation of
crowns and fixed partial dentures because
of
A. high viscosity.
B. low pH.
C. high solubility in saliva.
D. adverse pulp response.

Back 8

C. high solubility in saliva.

Front 9

Effective tissue displacement with elastic
impression materials can be accomplished
by
1. a firm tray material.
2. injection of the material into the
gingival sulcus.
3. placement of chemical-impregnated
cords into the gingival sulcus.
4. electrosurgical means.

Back 9

3. placement of chemical-impregnated
cords into the gingival sulcus.
4. electrosurgical means.

Front 10

A pontic exerting too much pressure
against the ridge will cause
1. fracture of the solder joints.
2. hypertrophy of the soft tissue.
3. crazing of the gingival portion of the
porcelain.
4. resorption of the alveolar bone.

Back 10

2. hypertrophy of the soft tissue.
4. resorption of the alveolar bone.

Front 11

Minor tooth movement to correct an
inclined fixed partial denture abutment
will
1. enhance resistance form of the
abutment.
2. reduce the possibility of pulpal
involvement.
3. direct occlusal forces along the long
axis of the tooth.
4. improve embrasure form.

Back 11

E. All the above.

Front 12

In a hygroscopic investment technique,
excess water in the investment mix will
result in a casting which
A. is over expanded.
B. is under expanded.
C. has deficient margins.
D. shows microporosity.
E. None of the above.

Back 12

B. is under expanded.

Front 13

Which of the following are characteristics
of restorative glass ionomer cements?
1. Release of fluoride.
2. Bonding to enamel.
3. Setting not affected by moisture.
4. Irritating to pulpal tissues.

Back 13

1. Release of fluoride.
2. Bonding to enamel.

Front 14

Where cavity preparations are extensive,
polycarboxylate cement can be used as a
base material because
A. its pH stimulates secondary dentin
formation.
B. it interacts with setting amalgam to
form a weak chemical union.
C. it is biocompatible with the pulp.
D. it is compressible when set.

Back 14

C. it is biocompatible with the pulp.

Front 15

Dental amalgam
A. is almost insoluble in the oral fluids.
B. has a satisfactory compressive
strength.
C. adapts well to the walls of the
prepared cavity.
D. All of the above.

Back 15

D. All of the above.

Front 16

The main reason for adding copper to a
dental amalgam alloy is to
A. increase expansion.
B. reduce tarnish resistance.
C. make amalgamation easier.
D. increase lustre.
E. reduce the tin-mercury phase.

Back 16

E. reduce the tin-mercury phase.

Front 17

Dental amalgams that are made from
alloys containing 6 percent copper,
compared to those made from alloys
containing 13 percent copper
1. have higher concentration of the tinmercury
phase.
2. are more resistant to tarnish and
corrosion.
3. demonstrate less creep or flow.
4. generally have lower compressive
strength.
5. demonstrate less marginal breakdown
in clinical service.

Back 17

1. have higher concentration of the tinmercury
phase.
4. generally have lower compressive
strength.

Front 18

Which of the following would occur if a
zinc containing amalgam is contaminated
with saliva during condensing?
1. No change in compressive strength
but lower tensile strength.
2. Increased expansion.
3. Reduced flow or creep.
4. Increased surface pitting.

Back 18

2. Increased expansion.
4. Increased surface pitting.

Front 19

Gold contributes which of the following
properties to a gold-copper alloy?
A. Corrosion resistance.
B. Increased strength.
C. Lowered specific gravity.
D. Increased hardness.

Back 19

A. Corrosion resistance.

Front 20

Inlay wax patterns should be invested as
soon as possible in order to decrease
distortion caused by
A. reduced flow.
B. drying-out of the wax.
C. release of internal stress.
D. continued expansion of the wax.

Back 20

C. release of internal stress.

Front 21

A maxillary complete denture exhibits
more retention and stability than a
mandibular one because it
1. covers a greater area.
2. incorporates a posterior palatal seal.
3. is not subject to as much muscular
displacement.
4. is completely surrounded by soft
tissue.

Back 21

1. covers a greater area.
2. incorporates a posterior palatal seal.
3. is not subject to as much muscular
displacement.

Front 22

The prime advantage of vacuum firing of
porcelain is
A. better colour.
B. less shrinkage.
C. more translucency.
D. increased strength.

Back 22

D. increased strength.

Front 23

Which of the following materials is most
radiolucent?
A. Calcium hydroxide.
B. Zinc phosphate cement.
C. Amalgam.
D. Gold foil.

Back 23

A. Calcium hydroxide.

Front 24

After initial setting, a chemically cured
glass ionomer cement restoration should
have a coating agent applied to
A. hasten the final set.
B. protect the cement from moisture.
C. retard the final set.
D. protect the cement from ultraviolet
light.
E. create a smooth finish.

Back 24

B. protect the cement from moisture.

Front 25

Generally, glass ionomer cements contain
A. zinc oxide and distilled water.
B. zinc oxide and polyacrylic acid.
C. fluoro aluminosilica powder and
orthophosphoric acid.
D. fluoro aluminosilica powder and
polyacrylic acid.

Back 25

D. fluoro aluminosilica powder and
polyacrylic acid.

Front 26

In taking a polysulfide impression for a
cast restoration in the maxilla, the tray
must
1. be rigid.
2. have occlusal stops.
3. cover the hard palate.
4. be coated with an adhesive cement

Back 26

1. be rigid.
2. have occlusal stops.
4. be coated with an adhesive cement

Front 27

The retentive arm of a combination clasp
(wrought wire retentive arm and cast
lingual arm) is better than a cast arm
because it
A. has a lower yield strength.
B. produces less stress on the abutment
tooth during removal and insertion.
C. can be used to engage deeper
undercuts because of a high modulus
of elasticity.
D. is economical to fabricate.

Back 27

B. produces less stress on the abutment
tooth during removal and insertion.

Front 28

All things being equal, which of the
following pontic designs is the most likely
to cause soft tissue irritation?
A. Polished gold.
B. Polished acrylic.
C. Polished porcelain.
D. Glazed porcelain.

Back 28

B. Polished acrylic.

Front 29

The curing of polysulphide and silicone
rubbers will not be complete throughout
the mass if
A. an equal amount of catalyst is not
present.
B. heat is not supplied to the reaction.
C. the mixture is not heterogenous.
D. the mixture is not homogenous.

Back 29

D. the mixture is not homogenous.

Front 30

Which of the following is NOT a direct
physiological response to additional forces
placed on abutment teeth?
A. Resorption of bone.
B. Increase in trabeculation.
C. Increase in width of cementum.
D. Increased density in cribiform plate.
E. Decrease in width of periodontal
ligament.

Back 30

E. Decrease in width of periodontal
ligament.

Front 31

The retention of an indirect, extra-coronal
restoration can be improved by
1. decreasing the taper of the
preparation wall.
2. lengthening the clinical crown.
3. adding grooves.
4. an antirotation key.

Back 31

E. All of the above.

Front 32

The function of the reciprocal clasp arm is
to
1. act as an indirect retainer.
2. stabilize the abutment teeth.
3. act as a direct retainer for the distal
base.
4. counteract any force transmitted by
the retentive arm.

Back 32

2. stabilize the abutment teeth.
4. counteract any force transmitted by
the retentive arm.

Front 33

The location of a crown margin is
determined by
1. esthetic requirements.
2. clinical crown length.
3. presence of caries.
4. presence of an existing restoration.

Back 33

E. All of the above.

Front 34

After initial setting, glass ionomer cements
should have a coating agent applied in
order to
A. hasten the final set.
B. protect the cement from moisture.
C. retard the final set.
D. protect the cement from ultraviolet
light.
E. create a smooth finish.

Back 34

B. protect the cement from moisture.

Front 35

Which of the following muscles has two
separate functions in mandibular
movement?
A. Masseter.
B. Geniohyoid.
C. External (lateral) pterygoid.
D. Buccinator.

Back 35

C. External (lateral) pterygoid.

Front 36

A lowering of serum calcium is the
stimulus for the endogenous release of
A. thyroid hormone.
B. adrenocortical hormone.
C. insulin.
D. parathyroid hormone.
E. adrenalin.

Back 36

D. parathyroid hormone.

Front 37

Collagen
A. is most common in hard tissues.
B. forms insoluble high tensile strength
fibres.
C. has a triple helical structure.
D. All of the above.

Back 37

D. All of the above.

Front 38

The success of remineralization of "white
spot" lesions is dependent upon the
1. pH of the saliva.
2. frequency of the cariogenic
challenge.
3. availability of mineral ions in saliva.
4. viscosity of the saliva.

Back 38

E. All of the above.

Front 39

Chronic alcoholism will
1. cause impairment of liver function.
2. increase tendency to hemorrhage.
3. delay healing.
4. decrease the effectiveness of local
anesthetics.

Back 39

E. All of the above.

Front 40

The main functions of fat soluble vitamins
are:
1. Vitamin E is an important antioxidant.
2. Vitamin A is important in the
formation of visual purple.
3. Vitamin D promotes intestinal
calcium and phosphate absorption.
4. Vitamin K catalyzes the synthesis of
prothrombin.
5. Vitamin A maintains the integrity of
mucous membranes.

Back 40

D. All of the above.

Front 41

Which of the following condition(s)
increase(s) susceptibility to dental caries?
1. Vitamin K deficiency during tooth
development.
2. Vitamin D deficiency during tooth
development.
3. Hereditary fructose intolerance.
4. Hyposalivation.

Back 41

2. Vitamin D deficiency during tooth
development.
4. Hyposalivation.

Front 42

Which of the following is the greatest risk
factor for rampant caries in children?
A. Frequent ingestion of
polysaccharides.
B. Frequent ingestion of high sucrosecontaining
foods.
C. Severe enamel hypoplasia.
D. Deficiency of vitamin D.

Back 42

B. Frequent ingestion of high sucrosecontaining
foods.

Front 43

Which of the following anaesthetic agents
is/are metabolized by plasma
cholinesterase?
1. Procaine.
2. Lidocaine (xylocaine).
3. Mepivicaine (carbocaine).
4. Prilocaine (citanest).

Back 43

1. Procaine.

Front 44

Long-acting barbiturates are mainly
excreted by the
A. salivary glands.
B. kidneys.
C. small intestine.
D. All of the above.
E. None of the above.

Back 44

B. kidneys.

Front 45

The selection of a vasoconstrictor for a
local anesthetic depends upon
A. the duration of the operation.
B. the need for hemostasis.
C. the medical status of the patient.
D. all of the above.

Back 45

D. all of the above.

Front 46

Warfarin (Coumadin®) acts by
A. preventing formation of
thromboplastin.
B. preventing fibrinogen conversion to
fibrin.
C. inhibiting the synthesis of
prothrombin in the liver.
D. incorporating ionic calcium.

Back 46

C. inhibiting the synthesis of
prothrombin in the liver.

Front 47

Streptomycin
A. enhances the activity of some
neuromuscular blocking agents.
B. can induce 8th cranial nerve damage.
C. is a broad-spectrum antibiotic.
D. All of the above.

Back 47

D. All of the above.

Front 48

When used for conscious sedation, nitrous
oxide may
1. produce signs of inherent myocardial
depression.
2. produce an indirect
sympathomimetic action.
3. cause the patient to sweat.
4. produce numbness of the extremities.

Back 48

2. produce an indirect
4. produce numbness of the extremities.

Front 49

Epinephrine is one drug used in the
management of an acute anaphylactic
reaction (Type I allergic reaction) because
it
A. relaxes bronchial muscles.
B. stimulates heart muscle and increases
heart rate.
C. increases systolic blood pressure.
D. produces vasoconstriction in many
vascular beds.
E. All of the above.

Back 49

E. All of the above.

Front 50

Which of the following, if left untreated, is
most likely to result in a periapical lesion?
A. Internal resorption.
B. Reversible pulpitis.
C. Acute suppurative pulpitis.
D. Chronic hyperplastic pulpitis.
E. Diffuse calcification of the pulp.

Back 50

C. Acute suppurative pulpitis.