MCQs in Prosthodontics

Chapter 5: Materials

  

 

1- In the selection of artificial teeth, which of the following should be selected 1st:

  1. Color of the tooth.
  2. Size of the tooth.
  3. Mold of the tooth.
  4. The order doesn't matter.
  5. None of the above.

 

 

 

 

The answer is: A

 

2- Which of the following types of materials should be used in dentures opposing natural teeth:

  1. Porcelain
  2. Ceramic
  3. Acrylic
  4. Metallic
  5. Any of the above.

 

 

 

 

 

The answer is: C

 

3- Which of the following types of teeth is bonded chemically to the acrylic denture bases:

  1. Porcelain teeth
  2. Ceramic teeth
  3. Acrylic teeth
  4. Metallic teeth
  5. All of the above.

 

 

 

 

 

The answer is: C

 

4- Which of the following types of materials should be used when the tooth should be excessively reduced in height because of small interarch distance:

  1. Porcelain teeth
  2. Ceramic teeth
  3. Acrylic teeth
  4. Metallic teeth
  5. All of the above.

 

 

 

 

 

The answer is: C

 

5- The proper arrangement of the maxillary and mandibular anterior and posterior teeth depends on the setting of:

  1. Maxillary central incisors.
  2. Maxillary lateral incisors.
  3. Maxillary canines.
  4. Mandibular central incisors.
  5. None of the above.

 

 

 

 

 

The answer is: A

 

6- Which of the following materials is most commonly used in the fabrication of the complete denture:

  1. Nylon
  2. Heat curing acrylic resins.
  3. Cold curing acrylic resins.
  4. Fluid resins.
  5. None of the above.

 

 

 

 

 

The answer is: B

 

 7- Which of the flowing materials should be ideally used for flasking:

  1. Plaster of Paris.
  2. Pumice
  3. Dental stone.
  4. Resins
  5. Any of the above.

 

 

 

 

 

The answer is: C

 

8- Dewaxing in boiling water should be done for maximum duration of:

  1. 3 to 5 minutes.
  2. 10 to 15 minutes.
  3. 15 to 25 minutes.
  4. 25 to 35 minutes.
  5. None of the above.

 

 

 

 

 

 

The answer is: A

 

9- How much power : liquid ratio is used in acrylic resin denture fabrication:

  1. 2:1
  2. 3:1
  3. 4:1
  4. 5:1
  5. 6:1

 

 

 

 

 

 The answer is: B

 

10- The compressive force applied during packing the acrylic resin dough should be applied:

  1. Rapidly
  2. All of sudden.
  3. Slowly
  4. Any of the above.
  5. None of the above.

 

 

 

 

 

The answer is: C

 

 11- The excess amount of resin dough, which comes out of flask during packing, is called as:

  1. Corrosion
  2. Flesh
  3. Flash
  4. Sellash
  5. None of the above.

 

 

 

 

 

The answer is: C

 

12- Before curing cycle begins, ideally the properly packed flask should be allowed to stand for:

  1. 5-10 minutes
  2. 10-15 minutes
  3. 15-20 minutes
  4. 30-60 minutes
  5. None of the above.

 

 

 

 

 

 The answer is: D

 

13- The specified curing cycle temperature and time is:

  1. 165°F and 9 hours
  2. 165°F for 90 minutes followed by 30 minutes at boil
  3. Both of the above
  4. Not specified
  5. None of the above.

 

 

 

 

 

The answer is: C

 

14- Fluid resin is a type of:

  1. Heat cure acrylic resin
  2. Chemically polymerized acrylic resin
  3. Hydrophilic polyacrylate
  4. High impact resin
  5. None of the above.

 

 

 

 

 

The answer is: B

 

15- Which of the following is a rubber reinforced acrylic:

  1. Hydrophilic polyacrylate
  2. Fluid resins
  3. High impact resins
  4. Visible light activated resins
  5. None of the above

 

 

 

 

 

 

The answer is: C

 

16- Which of the following materials does not contain methyl methacrylate:

  1. Fluid resin
  2. Rapid heat-polymerised resins
  3. Chemically polymerised resins
  4. Visible light activated composites
  5. None of the above

 

 

 

 

 

The answer is: D

 

17- Which of the following materials can be used as metal denture bases:

  1. Vulcanite
  2. Aluminum
  3. Chrome-cobalt
  4. All of the above
  5. None of the above

 

 

 

 

 

The answer is: D

 

18- Which of the following is a disadvantage of metal denture base:

  1. Good thermal conductivity
  2. More strength
  3. Dimensionally stable
  4. Greater weight
  5. None of the above

 

 

 

 

 

The answer is: D

 

19- Fillers are added to composite resin to increase:

  1. Expansion
  2. Hydrophilic properties
  3. Matrix deformation
  4. Wear resistance
  5. Working time

 

 

 

 

 

The answer is: D

 

20- Which of the following statements are correct regarding alginate impression materials?

  1. The setting time is controlled by the amount of potassium sulphate
  2. Phenylalanine may be added to provide a disinfection action
  3. Some alginates can be stored for up to 5 days in 100% relative humidity before significant dimensional changes occur
  4. The best way to delay the setting is by using a thinner mix
  5. Soaking the impression for 10 minutes in 0.5% hypochlorite is more effective than spraying with the same solution

 

 

 

 

 

The answer is: C

 

21- With regard to dental composite filling materials:

  1. They consist of three phases: resin, organic filler particles and a coupling agent coated on the filler particles
  2. The resin may be based on bis-GMA (dimethacrylate) oligomers
  3. Macrofilled composites contain particles of about 0.5–2 μm in diameter
  4. They usually contain fluoride
  5. Microfilled composites are harder to polish than macrofilled composites

 

 

 

 

 

 The answer is: B

 

 22- The position of the upper occlusal rim in the articulator is adjusted by:

  1. Arbitrary means
  2. By using a facebow
  3. By adjusting the intercondylar distance
  4. By adjusting the incisal pin
  5. Visually

 

 

 

 

 

 

The answer is: B

 

23- A loss in vertical dimension in complete denture will cause the mandible to move:

  1. Backward in relation to upper jaw
  2. Forward in relation to upper jaw
  3. No change in the position of the jaws
  4. Loss of vertical dimension is very rare
  5. In eccentric movements

 

 

 

 

 

The answer is: B

 

24- While recording the rest position of the mandible, the patient’s:

  1. Head should be upright and unsupported
  2. Head should be supported by the head rest
  3. Patient should be lying in repose position
  4. The neck should be extended
  5. Head can be in any position

 

 

 

 

 

The answer is: A

 

25- The correct bucco-lingual placement of the teeth plays an important role in phonation. What should be the relationship of teeth and tongue in pronouncing “t” and “d” sounds:

  1. The tongue will protrude forwards
  2. Contact of the tip of the tongue with the anterior palate and lingual surfaces of the maxillary anterior teeth
  3. The lips will contact with each other only
  4. Constricted palate form
  5. No relationship is present

 

 

 

 

 

The answer is: B

 

26- Balanced occlusion in complete denture is essential:

  1. For the patient to masticate properly
  2. For the dentures to have adequate retention
  3. To ensure even pressure in all parts of the arch, which maintains the stability of the dentures when the mandible is in centric and eccentric position.
  4. Balanced occlusion is not essential in complete dentures
  5. For aesthetic purposes

 

 

 

 

 

The answer is: C

 

 27- Tripoding is the method used:

  1. For giving clasp assemblies at 3 points
  2. For recording the relation of the cast to the surveyor
  3. To determine the areas on the tooth where the gingivally approaching clasp, occlusal rest of the reciprocal arm are going to be placed
  4. To have reproducible position of the cast on the surveyor
  5. To identify guide planes

 

 

 

 

 

 The answer is: D

 

28- What is the most suitable material for making impression of a partial dentate patient would be:

  1. Irreversible hydrocolloids
  2. Reversible hydrocolloid
  3. Elastomers
  4. Plaster of Paris
  5. Impression waxes

 

 

 

 

 

 

The answer is: C

 

29- What are the functions of an indirect retainer:

  1. to prevent horizontal dislodgement of the distal extension base of a removable partial denture
  2. to connect the parts of the prosthesis located on one side of the arch with those on the opposite side
  3. to prevent vertical dislodgement of the distal extension base of a removable partial denture
  4. to link the major connector and other parts of the prosthesis together
  5. it has no function

 

 

 

 

 

The answer is: C

 

30- A wrought wire clasp when used as a retainer:

  1. is less flexible than a cast clasp
  2. is not as tough as a cast clasp
  3. has a tensile strength that is at least 25% greater than that of the cast alloy from which it was made
  4. is not as adjustable as a cast clasp
  5. is never used as a retainer

 

 

 

 

 The answer is: C

 

 31- In the mesial rest, guide plane and i-bar design, reciprocation is achieved by:

  1. flexible plating
  2. minor connectors
  3. major connectors
  4. guide planes not extended around the vertical line of abutments
  5. retentive clasp arms

 

 

 

 

The answer is: B

 

32- All of the following are advantages of the gingivally approaching clasps as compared to occlusally approaching clasp, except:

  1. Less distortion of coronal contours
  2. Less tooth contact
  3. Cleaner
  4. Less bothersome to vestibular tissues
  5. Esthetically superior in most cases

 

 

 

 

The answer is: D

 

33- The reciprocal arm of the clasp assembly should:

  1. Always be on the lingual side
  2. Always be active, i.e. apply force to the tooth
  3. Be active when half of the denture has been Inserted
  4. Always be passive
  5. Reciprocation is not necessary

 

 

 

 

The answer is: D

 

34- Which is an appropriate procedure for disinfection of alginate impression:

  1. Complete immersion in bleach in a plastic bag for 1 hour
  2. Spraying for 30 seconds with an idophor and then wiping dry
  3. Placing in an autoclave on low temperature for 3 minutes
  4. Spraying with gluteraldehyde and sealing in a bag for 10 minutes
  5. Place under running water

 

 

 

 

 

The answer is: D

 

35- Which of the following elastomeric impression materials has the longest working and setting time:

  1. Polyether
  2. Polysulfide
  3. Condensation silicones
  4. Addition silicone
  5. soft acrylics

 

 

 

 

The answer is: B