Dental Materials

Question 1

Alloy of Mercury with silver, copper, tin, and zinc.

Answer 1

Amalgam

Question 2

Desirable features of Amalgam.

Answer 2

durable, comprehensive strength is similar to enamel, and relatively inexpensive.

Question 3

Undesirable features of amalgam.

Answer 3

unattractive, high thermal conductivity, dimensionally unstable, delayed expansion if contaminated by saliva, requires tooth support, fracturable by excessive occlusion, susceptible to galvanism when new.

Question 4

What reduces the rate of corrosion to amalgam?

Answer 4

Polishing

Question 5

How are overhang formation avoided?

Answer 5

Using a properly placed band and wedge. Detect overhang with explorer.

Question 6

How is polymerization typically activated?

Answer 6

Fiber-optic light

Question 7

Steps to placing a sealant.

Answer 7

Pumice, rinse, isolate, etch, rinse, dry, apply, remove excess, and polymerize.

Question 8

Most common filler particles of a composite?

Answer 8

Silicates, quartz, or glass.

Question 9

What is added to a composite for radiopacity?

Answer 9

Barium or Strontium

Question 10

This has an exothermic reaction on mixing (use cool glass slab).

Answer 10

Zinc phosphate cement

Question 11

This binds to dentin and releases fluoride.

Answer 11

Glass ionomer cement

Question 12

This is commonly used for temporary cementation. Orange solvent typically used to clean the contaminated instruments of this material.

Answer 12

Zinc Oxide Eugenol

Question 13

What is Agar?

Answer 13

Reversible hydrocolloid, Undergoes a physical reaction only, and susceptible to imbibition and syneresis.

Question 14

What is Alginate?

Answer 14

Irreversible hydrocolloid, undergoes a chemical reaction, and susceptible to imbibition and syneresis.

Question 15

What is Elastomeric?

Answer 15

Fkexible material

Question 16

What materials set by polymerization EXCEPT?

Answer 16

Hydrocolloid

Question 17

What is superior to beta (plaster) as a material?

Answer 17

Alpha (stone)

Question 18

What is used to make a orthodontic model?

Answer 18

Plaster

Question 19

What is used to make a study model/working model?

Answer 19

Stone

Question 20

What is used to make a crown and bridge die or model?

Answer 20

Improved stone or diestone

Question 21

What modifies the working time?

Answer 21

Add borax to slow set, add potassium sulfate to accelerate set.

Question 22

Used for cast restorative patterns

Answer 22

Inlay and casting wax

Question 23

Useful in removable prosthetic procedures.

Answer 23

Baseplate wax

Question 24

Useful to obtain occlusal records.

Answer 24

Bite registration wax

Question 25

Used in pouring models

Answer 25

Boxing wax

Question 26

Becomes sticky when heated, used to attach models.

Answer 26

Sticky Wax

Question 27

Used to modify the shape of impression trays and cushion braces.

Answer 27

Utility Wax

Question 28

What does precious alloys contain?

Answer 28

noble metals

Question 29

What does non precious alloys contain?

Answer 29

Base metals

Question 30

What can gold be polished with intra-orally?

Answer 30

Tin Oxide

Question 31

What can gold be polished with extra-orally?

Answer 31

Rouge

Question 32

What may prosthesis be?

Answer 32

cylindrical or have a blade shape.

Question 33

What are implants?

Answer 33

Endosteal

Question 34

Whats the leading cause of implant failure?

Answer 34

MOBILITY, lack of osseo-integration, and inadequate bone.

Question 35

Contraindications to implant placement?

Answer 35

Inadequate bone, uncontrolled periodontal disease, smoking, infection, and biphosphonates.

Question 36

Active ingredient in Tartar control toothpastes?

Answer 36

Pyrophosphate

Question 37

Active ingredient in gum care toothpastes?

Answer 37

Triclosan (antimicrobial agent)

Question 38

Active ingredient in desensitization toothpastes?

Answer 38

Potassium nitrate, sodium citrate, or strontium chloride.

Question 39

Active ingredient in bleach or tooth-whitening?

Answer 39

Carbamide peroxide or hydrogen peroxide